Question:
Both x and y vary inversely with each other. When x is 10, y is 6, which of the following is not a possible pair of corresponding values of x and y?
(a) 12 and 5
(b) 15 and 4
(c) 25 and 2.4
(d) 45 and 1.3
Solution:
(d) 45 and 1.3
Explanation: since x and y vary inversely, so
xy = k (constant)
Putting the value of x and y, we get;
10×6 = 60
Now if we observe the options available;
Option (a) – 12 and 5 – 12×5 = 60
Option (b) – 15 and 4 – 15×4 = 60
Option (c) – 25 and 2.4 – 25×2.4 = 60
Option (d) – 45 and 1.3 = 45×1.3 = 58.3
Therefore, option (d) is not a possible pair of corresponding values of x and y