9514 1404 393
Answer:
9.1 cm
Explanation:
Corresponding sides of similar triangles are proportional.
PQ/PR = AB/AC
PQ/21.7 = 5.2/12.4 . . . . . . . . . . . . . . fill in the given values
PQ = 21.7(5.2/12.4) . . . . . multiply by 21.7
PQ = 9.1 . . . cm