Question

x and y vary inversely, and x=50 when y=5. find y when x=10. what is k?

Answer 1

y varies inversely with x.
⇒ y = k/x

When y = 5, x = 50
5 = k/50
k = 50 x 5 = 250

Equation: y = 250/x

When x = 10
y = 250/10 = 25

Answer: k = 250, y = 25 when x = 10