Question

Pls help me

1. If y = 24 when x = 2, find y when x is 9.
2. If y = 18 when x = 25, find y when x is 30.
3. If y = 10 when x = 1, find y when x is 20.
4. If y = 10 when x = 21, find x when y is 35

Answer 1

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Answer:

1. direct: 108; inverse: 16/3
2. direct: 108/5; inverse: 15
3. direct: 200; inverse: 1/2
4. direct: 147/2; inverse: 6

Explanation:

We cannot tell what kind of proportionality to assume here.

If x and y are directly proportional, multiplying one by a factor will multiply the other by the same factor.

If x and y are inversely proportional, multiplying one by a factor will divide the other by the same factor.

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1. Given (x, y) = (2, 24). Direct: y = 9/2(24) = 108.

Inverse: y = 2/9(24) = 16/3

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2. Given (x, y) = (25, 18). Direct: y = 30/25(18) = 108/5.

Inverse: y = 25/30(18) = 15.

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3. Given (x, y) = (1, 10). Direct: y = 20/1(10) = 200.

Inverse: y = 1/20(10) = 1/2.

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4. Given (x, y) = (21, 10). Direct: x = 35/10(21) = 147/2.

Inverse: x = 10/35(21) = 6.