Question

Q is directly proportional to r. q is 76 when r is 20. work out q when r is 45.

Answer 1

q=171

Explanation:

Hello there!

In this explanation k is constant and it means that q is some constant amount bigger than r.

q=kr

76=k×20

76÷20=k

k= 3.8

q=3.8r

q=3.8×45

q=171

Answer 2

q α r
q=kr
thus
k=q/r
when r=20, q=76
hence
k=76/20=
q=76/20r
when r=45 the value of q will be:
q=76/20×45
q=171