18
First you want to change the 20% into a decimal which is .20
Next you want to multiply 90 by .20 because that will give you the answer for 20% of 90
90x.20=18
Hope that helps
v varies directly with height means
v/h=k were k is a constant
or also h/v=k where k is a constant (this is a different k than previous)
so if h=12 and v=300 then
h/v=12/300=1/25=k
so the relationhip could be h/v=1/25
if you di v/h, then
v/h=300/12=25/1=25=k
so the relationship could be v/h=25
