please answer these please??(studyguide)

6. 6 to 8 and 18 to x

A.20
B.22
C.24

7.9/36 and x/4

A.1
B.4
C.9

8.42/22 and 21/x

A.12
B.11
C.10

9.x/7 and 5/1

A.25
B.30
C.35

10.20/x and 4/8

A.35
B.40
C.48

Hey, it is time you learned to do these. List your answers.