Answer:
QR = 30
Step-by-step explanation:
GHI ~ PQR means that PQR is the same shape and length ratios as GHI but is a different size.
All of the leg lengths of GHI are multiplied by something to get the leg lengths of PQR.
You're given the leg lengths 12 and 20. So you need to find out what 12 is multiplied by to get to 20. 12 * 5/3 = 20.
So multiply 5/3 by the other leg length 18.
18 * 5/3 = 30
So QR = 30
