Question

Given that A varies directly as B and inversely as C and that; A=12 when B=3 and C=2. Find B when A=10 and C=1.5​

Answer 1

B = 1.875

Explanation:

given that A varies directly as B and inversely as C then the equation relating them is

A =
`(kB)/(C)` ← k is the constant of variation

to find k use the condition A = 12 when B = 3 and C = 2 , then

12 =
`(3k)/(2)` ( multiply both sides by 2 to clear the fraction )

24 = 3k ( divide both sides by 3 )

8 = k

A =
`(8B)/(C)` ← equation of variation

when A = 10 and C = 1.5 , then

10 =
`(8B)/(1.5)` ( multiply both sides by 1.5 )

15 = 8B ( divide both sides by 8 )

1.875 = B