Question

If x and y vary directly as each other and x= 7 when y=21. Find x when y = 27. *

Answer 1

Answer:

If x and y vary directly and when x is 7, y is 21 , then when y= 27, x = 9

Step-by-step explanation:

Given

x and y vary directly.

And if x= 7, y=21

Ratio of x : y = 7 : 21 = 1 : 3

So y is 3 times x

If y= 27, then x= 27/3 = 9

So for y= 27, x= 9

Answer 2

Answer:

35 and 25

Step by step explanation:

x and y are directly proportional.

x ∝ y

If x = 10 and y = 14, then;

10 ∝ 14 or 5 ∝ 7

Now, if we compare,

(a) 25 ∝ 35 = 5∝7

(b) 35 ∝ 25 = 7 ∝ 5

(c) 35 ∝ 49 = 5 ∝ 7

(d) 15 ∝ 21 = 5 ∝ 7

Therefore, option (b) is not a possible pair of corresponding values of x and y.

hence answer is 35 and  25