I set equations for all of them.
x=the missing value
(#3) 96/15=8/x Cross multiply
96x=120 Divide by 96 on both sides
x=1.25
(#4) 15/x=75/8 Cross multiply
75x=120 Divide both sides by 75
x=1.6
(#5) x/96=6/8 Cross multiply
8x=576 Divide both sides by 8
x=72
(#7) 3/42=8/x Cross multiply
3x=336 Divide both sides by 3
x=112
(#8) x/12=9/84 Cross multiply
84x=108 Divide both sides by 84
x=1.29
(#9) 16/x=128/13 Cross multiply
128x=208 Divide both sides by 128
x=1.625
