Question

give 3 examples each of direct variation and inverse variation.

Answer 1

direct variation
eg1-cost of six mineral water bottles is rs 90.how many mineral water bottles can be bought for rs 225?
solution-Let the no of bottles for rs 225=x,then ,we have
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no of mineral water bottles | 6 | x   |
cost (in rupees)                  | 90|225|
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6/90 =x/225
x=6*225/90
x=15
15 mineral water bottles can be bought for rs 225.

eg2-a man deposits a sum of rs 5000 in a bank and earned an interest of  rs 600 in two years. how much interest would a deposit of rs 8000 earn in the same period?(rate of interest being the same.)
solution-let interest earned on rs 8000=rs x
thus , we have ,
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money deposited(in rs) | 5000 | 8000 |
interst earned     (in rs) | 600    | x       |
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5000/600=8000/x
x=960
interest on rs 8000 would be rs 960.

eg3- fill the missing terms in the following table , if x & y vary directly.
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x| 6 | 8  | 12 | 21 |
y|18| 24| 36 |  63|
        ---- ----
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Inverse variation
eg1-if 52 men can do a piece of work in 35 days.In how many days will 28 men complete the same work?
solution-let 28 men do the same work in x days.
we have
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no of men | 52 | 28 |
days         | 35 | x   |
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hence,52*35=28*x
x=52*35/28
x=65
28 men will do the same work in 65 days.
eg-2 in a camp,there is enough provision for 500 students for 30 days.if 100 more students join the camp , for how many days will the provition last now?
solution-let the number of days =x
now no of students in the camp=500+100=600
thus,we have,
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no of students| 500 | 600 |
no of days      | 30   | x     |
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500*30=600*x
x=500*30/600
x=25
hence,the provision will last for 25 days.
eg3-in the following table, a & b vary inversly.fill the missing values.
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a|7|14|28|
      ---
b|8|4 | 2  |
          ---
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please mark it as brainliest
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