A quantity, t, varies inversely with a quantity, r. Ift = 6, then r = 5.

What is the constant of variation?

k=

What is the equation that represents this variation?

rt =

What is the value of t when r = 15?

Step-by-step explanation:

if t varies inversely proportional as r, then,

t ∞ 1/r

t = k. 1/r

t = k/r

substitute t = 6 and r = 5 into the equation above

6 = k/5

k = 5 x 6 = 30

the equation that represents this variation is given by,

t = 30/r

tr = 30

when r = 15,

t = 30/15

t = 2