Africa: Social and Economic Activities

Africa is multi-racial continent because there are more than 800 black African races. The population of the modern time also includes white people from other continents. This note has information about African people and their economic activities.

Summary

Africa is multi-racial continent because there are more than 800 black African races. The population of the modern time also includes white people from other continents. This note has information about African people and their economic activities.

Things to Remember

  • Africa is multi-racial continent because there are more than 800 black African races.
  • The second group of people is called Bushmen who live in the Kalahari.
  • Wheat is also cultivated in African savannas.
  • Commercial farming is run by the government, multinational companies and rich people.
  • Cattle and sheep are reared in South Africa, where there are temperate grasslands.
  • Large scale industries are not well developed in Africa.
  • Africa is rich in bio-diversity with the majestic and magnificent landscape.

MCQs

No MCQs found.

Subjective Questions

Q1:

If a motor car can travel 80 km and 8l of petrol ,
(i) how many km will the car travel for 5l petrol ?
(ii) find the quantity of petrol required to travel 30 km ?


Type: Short Difficulty: Easy

Show/Hide Answer
Answer: <p>Here , for 8 litres petrol a car can travel 80 km<br>For 1 litre petrol a car can travel \(\frac{80}{8}\) km<br>For 5 litres petrol a car can travel \(\frac{80}{8}\) \(\times\) 5 km = 50 km. <br>Hence , a car can travel 50 km. for 5l of petrol. <br><br>(ii) Here, to travel 80 km, the car requires 8 l of petrol. <br>To travel 1 km, the car requires \(\frac{8}{80}\)l of petrol<br>To travel 30 km , the car requires \(\frac{8}{80}\) \(\times\) 30 = 3l of petrol. <br>Hence, 3 litres of petrol is needed to travel 30 km. Ans.</p>

Q2:

Three people can finish making a roof of a house in 5 days. In how many days can it be done by 5 people ?


Type: Short Difficulty: Easy

Show/Hide Answer
Answer: <p>Here , 3 people can make a roof in 5 days. <br>1 people can make a roof in 5 \(\times\) 3 days.</p> <p>\(\therefore\) 5 people can make a roof in \(\frac{5 \times 3}{5}\) = 3 days. <br>Hence , 5 people can make the roof in 3 days.</p>

Q3:

In how many days a piece of work which is done by 5 people in 6 days be done by 15 people ? Likewise , how mnay people can complete it in 3 days ?


Type: Short Difficulty: Easy

Show/Hide Answer
Answer: <p>Let the required days be denoted by x and the given data be arranged in a table below.</p> <table width="324"><tbody><tr><td>Workers</td> <td>Days</td> </tr><tr><td>5<br>15</td> <td>6<br>x</td> </tr></tbody></table><p>Now , \(\frac{x}{6}\) = \(\frac{5}{15}\)</p> <p>or , x = \(\frac{5}{15}\) \(\times\) 6 = 2days. <br>Again , let the require of workers can be denoted by x and the data by x and the data be arranged as shown below. </p> <table width="305"><tbody><tr><td>Workers</td> <td>Days</td> </tr><tr><td>5<br>x</td> <td>6<br>3</td> </tr></tbody></table><p>Now , \(\frac{x}{5}\) = \(\frac{6}{3}\)</p> <p>or , x = \(\frac{6}{3}\) \(\times\) 5 = 10<br>Hence , the required number of people = 10</p>

Q4:

20 boys or 30 girls can finish a piece of work in 27 days . If 10 boys and 12 girls do the same work together , how many days will be required ?


Type: Short Difficulty: Easy

Show/Hide Answer
Answer: <p>Here , 20 boys = 30 girls<br>or , 1 boys = \(\frac{30}{20}\) girls<br>or , 10 boys = \(\frac{30}{20}\) \(\times\) 10 = 15 girls.</p> <p>Here , 10 boys and 12 girls = 15 girls + 12 girls = 27girls<br>Let , 27 girls can do a piece of work in x days. </p> <table width="338"><tbody><tr><td>Girls</td> <td>Day</td> </tr><tr><td>30<br>27</td> <td>27<br>x</td> </tr></tbody></table><p>Now , \(\frac{x}{27}\) = \(\frac{30}{27}\)<br>\(\therefore\) x = \(\frac{30 \times 27}{27}\) days = 30 days<br><br>Hence , 27girls or 10 boys and 12 girls can finish the work in 30 days</p>

Q5:

15 chairs and  2 tables cost Rs. 4000. If the cost of 10 chairs and 4 tables are equal then what will be the total cost of 12 chairs and 3 tables ?


Type: Long Difficulty: Easy

Show/Hide Answer
Answer: <p>Here , 10 chairs = 4 tables <br>1 chairs = \(\frac{4}{10}\) tables<br>15 chairs = \(\frac{4}{10}\) \(\times\) 15 tables<br>15 chairs = 6 tables<br><br>Again , 12 chairs = \(\frac{4}{10}\) \(\times\) 12 = \(\frac{24}{5}\)<br>Now , 15 chairs +| 2 tables = 6 tables + 2 tables = 8tables. <br>and 12 chairs + 3 tables = \(\frac{24}{5}\) tables + 3 tables<br> = ( \(\frac{24}{5}\) + 3 ) tables. <br> = \(\frac{39}{5}\) tables. <br><br>Here , Cost of (15 chairs + 2 tables) = Rs. 4000<br>or , Cost of 8 tables = Rs 4000<br>or , Cost of 1 table = Rs. \(\frac{4000}{8}\)<br>or , Cost of \(\frac{39}{5}\) tables = Rs.\(\frac{4000}{8}\) \(\times\) \(\frac{39}{5}\) = Rs. 3900<br><br>Hence , total cost of \(\frac{39}{5}\) tables or of (12 chairs + 3 tables) in Rs. 3900 Ans. </p>

Q6:

If walking 9 hours a day  , a person walks 270 km in 4  days  then in 5 \(\frac{1}{4}\) days , if he wants to walk 315 km then how many hours a day should he walk  ?


Type: Long Difficulty: Easy

Show/Hide Answer
Answer: <p>Let a perosn should walk x hrs\day to travel 315 km in 5 \(\frac{1}{4}\) days. </p> <table width="419"><tbody><tr><td>Distance</td> <td>Hrs.</td> <td>Days</td> </tr><tr><td>270<br>315</td> <td>9<br>x</td> <td>4<br>\(\frac{21}{4}\)</td> </tr></tbody></table><p>Now , <br>\(\frac{x}{9}\) = \(\frac{315}{270}\) \(\times\) 4 \(\times\) \(\frac{4}{21}\)<br>Hence , x = \(\frac{315 \times 16 \times 9}{270 \times 21}\) = 8hrs.</p>

Q7:

From one cylinder gas , 10 gas lighter can be lit for 4 hours every evening for 15 days. So , for how many days 12 gas lighters can be lit for 6 hours every evening ?


Type: Long Difficulty: Easy

Show/Hide Answer
Answer: <p>Let , 12 gas lighter can be lit for 6 hours every evening for x days.</p> <table width="452"><tbody><tr><td>Gas lighter</td> <td>Hours</td> <td>Days</td> </tr><tr><td>10<br>12</td> <td>4<br>6</td> <td>15<br>x</td> </tr></tbody></table><p>By the rule of variation , <br>\(\frac{x}{15}\) = \(\frac{10}[12]\) \(\times\) \(\frac{4}{6}\)<br><br>\(\therefore\) x = \(\frac{10 \times 4 \times 15}{12 \times 6}\) = \(\frac{25}{3}\) = 8 \(\frac{1}{3}\)</p> <p></p>

Q8:

A piece of work was given to the contractor to finish in 40 days. After 24  days  , only half of the work was completed and then additional labourers were employed and the work was finished in time  , How many labourers were employed at first ?


Type: Short Difficulty: Easy

Show/Hide Answer
Answer: <p>Let the numbers of labourers employed at first = x<br>Remaining days = 40 - 24 = 16<br>Work done in 24 days = \(\frac{1}{2}\) <br>Remaining work after 24 days = 1- \(\frac{1}{2}\) = \(\frac{1}{2}\)<br>Now , arranging the given informations , we get </p> <table width="421"><tbody><tr><td>Workers</td> <td>Days</td> <td>Work</td> </tr><tr><td>x<br><br>X + 16</td> <td>24<br><br>16</td> <td>\(\frac{1}{2}\)<br><br>\(\frac{1}{2}\)</td> </tr></tbody></table><p>So , by the rule of variation <br>\(\frac{x+16}{x}\) = \(\frac{24}{16}\) \(\times\) \(\frac{1 / 2}{1 / 2}\)<br>or , \(\frac{x + 16}{x}\) = \(\frac{3}{2}\)<br>or , 2x + 32 = 3x<br>or , 3x - 2x =32<br>\(\therefore\) x= 32. <br>Hence , the required numbers of labourers = 32 . </p>

Q9:

A contractor employed 9 labourers to complete the work in 17 days . After 8  days , only \(\frac{2}{5}\) of wo
Type: Short Difficulty: Easy

Show/Hide Answer
Answer: <p>Here , remaining days after 8 dyas = 17 - 8= 9<br>Remaining work after 8 dyas = 1- \(\frac{2}{5}\) = \(\frac{5-2}{5}\) = \(\frac{3}{5}\) part. <br>Let , x labourers be required to complete the remaining work in remaining days. </p> <table width="459"><tbody><tr><td>Labours</td> <td>Works</td> <td>Days</td> </tr><tr><td>9<br><br><br>x</td> <td>\(\frac{2}{5}\)<br><br><br>\(\frac{2}{5}\)</td> <td>8<br><br><br>9</td> </tr></tbody></table><p>Now , \(\frac{x}{9}\) = \(\frac{8}{9}\) \(\times\) \(\frac{3/5}{2/5}\)<br>or , x= \(\frac{8}{9}\) \(\times\) \(\frac{3}{5}\) \(\times\) \(\frac{5}{2}\) \(\times\) 9= 12<br><br>Hence , 12 labourers are required to complete the work in remeining days. <br>Again , additional labourers = 12 - 9 = 3 Ans.</p>

Q10:

Toa grou
Type: Short Difficulty: Easy

Show/Hide Answer
Answer: <p>Here , after 20 days , the remaining food is availabel for 1000 soldiers for 70 - 20 = 50 days. Let , the remaining food is available for 1000 + 200 = 1200 soldiers for x days , if other 200 soldiers were added. </p> <table width="395"><tbody><tr><td>Soldiers</td> <td>Time</td> </tr><tr><td>1000<br>1200</td> <td>50 days<br>x</td> </tr></tbody></table><p>Now , \(\frac{x}{50}\) = \(\frac{1000}{1200}\)<br><br>\(\therefore\) x = \(\frac{1000 \times 50 }{1200}\) = 41 \(\frac{2}{3}\) days. Ans.</p>

Q11:

To a group of 600 soldiers , food was provided fr\or 50 days. If after 15 days , 180 soldiers abandoned the group how many days will the remaining food lasts for ?


Type: Short Difficulty: Easy

Show/Hide Answer
Answer: <p>Let , the remaining food last for x days. Now arranging the above information in a table as below :</p> <table width="545"><tbody><tr><td>Soldiers</td> <td>Time Period</td> <td>Note: After 15 dyas , the <br>remaining food is availabel <br>for 600 soldiers for 35 days. </td> </tr><tr><td>600<br><br>600 -180</td> <td>50 - 15 = 35<br><br>x</td> <td></td> </tr></tbody></table><p>Now , \(\frac{x}{35}\) = \(\frac{600}{420}\) <br><br>\(\therefore\) x =- \(\frac{600 \times 35}{420}\) = 50 days. Ans. </p>

Q12:

A contractor employed 40 labourers to construct a house in 33 days.
(i) . if he employed 60 labourers to do the same work , in how many days will the work be completed ?
(ii). how many labourers will be required to complete the work in 10 days ?


Type: Long Difficulty: Easy

Show/Hide Answer
Answer: <p>Here , 40 labourers can construct a house in 33 days. <br>1 labourer can constructa house in 33 \(\times\) 40 days. <br>60 labourers can construct a house in \(\frac{33 \times 40}{60}\) = 22 days. <br> Hence , it will take 22 days for 60 labourers to finish the work. <br><br>(ii). Here , in 33 days , 40 labourers are required to construct the house. <br>In 1 day , 40 \(\times\) 33 labourers are required to construct the house. <br>In 10 days \(\frac{40 \times 33}{10}\) = 132 labourers are required to construct the house. <br><br>Hence , 132 labourers will be required to complete the work in 10 days.</p>

Q13:

To complete a piece of work in 10 days , 30 people should work at the rate of 12 hours a day . If 40 people have to finish it in 18 days , how many hours should the work be done per day ?


Type: Short Difficulty: Easy

Show/Hide Answer
Answer: <p>Let the work should be done x hours per day. Now , arranging the given data in a table as follows </p> <table width="495"><tbody><tr><td>People</td> <td>Days</td> <td>Hours</td> </tr><tr><td>30<br>40</td> <td>10<br>18</td> <td>12<br>x</td> </tr></tbody></table><p>Now , \(\frac{x}{12}\) = \(\frac{30}{40}\) \(\times\) \(\frac{10}{18}\)<br><br>\(\therefore\) x = \(\frac{30 \times 10 \times 12}{40 \times 18}\) = 5 hours. <br><br>Hence , the required hours = 5hrs/days.</p>

Q14:

If 9 pumps can pull 425l of water in 10 minutes . What amount of water will be pulled by 6 pumps in 12 minutes ?


Type: Short Difficulty: Easy

Show/Hide Answer
Answer: <p>Let , 6 pumps can pumps can pump x litres of water in 12 minutes. Now arranging the given data in a table as shown below :<br><br></p> <table width="462"><tbody><tr><td>No. Of pumps</td> <td>Time</td> <td>Quantity (in ltrs)</td> </tr><tr><td>9<br><br>6</td> <td>10 minutes<br><br>12 minutes</td> <td>425l<br><br>x</td> </tr></tbody></table><p>Now , \(\frac{x}{425}\) = \(\frac{6}{9}\) \(\times\) \(\frac{12}{10}\)<br><br>\(\therefore\) x = \(\frac{6 \times 12 \times 425}{9 \times 10}\) = 340l .Ans.</p>

Q15:

8 labourers can paint a room of area of 200 m2 in 5 days. What area of room can be painted in 10 days by 6 labourers ?


Type: Short Difficulty: Easy

Show/Hide Answer
Answer: <p>Let , in 10 days can paint a room of area off x m<sup>2 </sup>. Now arranging the given data in a table as below :</p> <table width="376"><tbody><tr><td>Labourers</td> <td>Days</td> <td>Area</td> </tr><tr><td>8<br><br>6</td> <td>5<br><br>10</td> <td>2000<br><br>x</td> </tr></tbody></table><p>Now , \(\frac{x}{2000}\) = \(\frac{6}{8}\) \(\times\) \(\frac{10}{5}\) <br><br><br>\(\therefore\) x = \(\frac{6 \times 10 \times 2000}{8 \times 5}\) = 3000m<sup>2 </sup></p>

Q16:

A person takes 4 dyas to walk 56 km. How many days will he take to walk 154 km ?


Type: Short Difficulty: Easy

Show/Hide Answer
Answer: <p>Here , a person walks 56 km in 4 days. <br>\(\therefore\) A person walks 1 km in \(\frac{4}{56}\) days. <br>\(\therefore\) A person walks 154 km in \(\frac{4}{56}\) \(\times\) 154 = 11 days. <br><br>Hence , a person will take 11 days to walk 154 km.</p>

Q17:

The amount of money which buy 12 kg of sugar when the price of 1 kg of sugar is 27.50 , can now buy only 10 kg of sugar. Calculate the amount of money required to buy 12  kg of sugar now ?


Type: Short Difficulty: Easy

Show/Hide Answer
Answer: <p>Here , the cost of 1 kg sugar = Rs. 27.50<br>Cost of 12 kg sugar is 27.50 \(\times\) 12<br>or , Cost of 12 kg sugar = Rs. 330<br><br>By question , <br>Cost of 10 kg sugar = Rs. 330<br><br>The cost of 1 kg sugar = Rs. \(\frac{330}{10}\) <br><br>Cost of 12 kg of sugar = \(\frac{330}{10}\) \(\times\) 12 = Rs. 396. <br><br>Hence , the cost of 12 kg of sugar is Rs. 396.</p>

Q18:

12 girls or 8 boys can finish a piece of work in 3 days. Now , in how many days can 4 boys and 6 girls finish the same work ?


Type: Short Difficulty: Easy

Show/Hide Answer
Answer: <p>Here , 12 girls = 8 boys<br><br>or , 1 girl = \(\frac{8}{12}\) boys}<br><br>or , 6 girls = \(\frac{8}{12}\) \(\times\) 6 boys = 4 boys<br><br>\(\therefore\) 4 boys and 6 girls = 4 boys + 4 boys = 8 boys. <br><br>Now , By question 8 boys can finish a work in 3 days. But 4 boys and 6 girls are equivalent to 8 days. Hence , 4 boys and 6 girls can finish the same work in 3 days. Ans. </p>

Q19:

A sack of 100 kg rice can be transported to a distance of 50 km at Rs. 15. At the same rate if 80 kg of rice sack is to be transported 75 km , then  how much will it cost ?


Type: Long Difficulty: Easy

Show/Hide Answer
Answer: <p>Let , the requied cost be Rs.x</p> <table width="386"><tbody><tr><td>Weight</td> <td>Distance</td> <td>Cost</td> </tr><tr><td>100 kg<br>80 kg</td> <td>50 km<br>75 km</td> <td>Rs.15<br>x</td> </tr></tbody></table><p>Then , \(\frac{x}{15}\) = \(\frac{80}{100}\) \(\times\) \(\frac{75}{50}\)<br><br>or , x = \(\frac{80 \times 75 \times 15}{100 \times 50}\) = 18. <br><br>Hence , Rs.18 is required to transport 80 kg of rice to a distance of 75 km.</p>

Q20:

A bread factory decreased the weight of bread due to the increase in price of flour to keep the price of bread fixed. If the weight of bread was 180 gm when the price of flour per quintal was Rs. 1500, what should be the decrease in the weight of bread when the price of flour is Rs. 1800 per quintal?


Type: Long Difficulty: Easy

Show/Hide Answer
Answer: <p>We can put the given data in table as shown below.<br>Let x be the weight of the bread when price of the flour was Rs. 1800 per quintal</p> <table width="365"><tbody><tr><td>Weight</td> <td>Price</td> </tr><tr><td>180 gm<br>x</td> <td>Rs. 1500<br>Rs.1800</td> </tr></tbody></table><p>By the rule of variation , <br>\(\frac{x}{180}\) = \(\frac{1500}{1800}\)<br>\(\therefore\) x = \(\frac{1500 \times 1800}{1800}\) = 150<br><br>\(\therefore\) The weight of a bread = 150 gm<br><br>Hence , the decrease in the weight of a bread = (180- 150) gm = 30gm Ans.</p>

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Africa: Social and Economic Activities

Africa: Social and Economic Activities

Africa is multi-racial continent because there are more than 800 black African races. The population of the modern time also includes white people from other continents. The native people are dark complexioned and curly-haired. They live in Ethiopia and the south of the Sahara. The second group of people is called Bushmen who live in the Kalahari. They are short and their skin is yellow. They live on hunting animals and gathering wild fruits and nuts. Their main occupations are hunting animals and collecting fruits. The fourth group is the Masai tribesmen who are tall. The life in the East Africa is rearing animals.

The Arabs invaded Africa and settled there in the seventh century. They are mainly traders. After them came British, Belgians, French, Dutch and Germans. The British established their colonies here. Africa is the second largest continent but it is not very developed. Poverty, illiteracy, famine, epidemics and civil wars are the main reasons for the under development.

Agriculture

Agriculture is not much developed in Africa. They grow both food crops and cash crops. Maize is grown in Savanna region, Egypt and South Africa. Another important food crop is Paddy which is cultivated in the eastern tropical coast. Wheat is also cultivated in the African savannas. The Nile Valley, Algeria, Tunisia, Morocco and Cape Province are also important for wheat cultivation.

The main cash crops include cotton, tea, coffee and cocoa. The chief regions where cotton is produced are the Nile Valley, Uganda, Nigeria, Mozambique and Malawi. Coffee is cultivated in Ethiopia, Uganda, Zaire and West Africa. Tea is cultivated on the slopes of the eastern highlands. Ghana and Nigeria are the main producers of cocoa.

Commercial Farming

Commercial farming is run by the government, multinational companies and rich people. It is conducted in Kenya, Tanzania, Botswana, South Africa and Lesotho.

Such agricultural farms are called Estates, where banana, coffee, cocoa, rubber, tobacco and sisal are grown.

Animal Rearing

Animal Rearing is an important occupation in Africa. Cattle and sheep are reared in South Africa, where there are temperate grasslands.

South Africa exports good quality wool. Cattle and sheep are also raised in Algeria, Morocco and Tunisia.

Industries

Large scale industries are not well developed in Africa. Most industries are agro-based and include textile mills, oil mills, hide processing and rubber factories.

There are also some minerals based industries like iron, steel, copper and aluminum industries.

Tourism

Africa is rich in bio-diversity with the majestic and magnificent landscape. National parks have been established to attract tourists and to preserve wildlife. Africa is also known as the zoo of the world.

Millions of tourists visit these national parks. Many valuable animals die due to lack of fodder and water. They have to be protected from poachers, the illegal hunters.

Lesson

Geographical Studies of our Earth

Subject

Social Studies

Grade

Grade 10

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