Question

A varies inversely as the square root of x. If x=15, then A=45. Find A if x=30 (nearest tenth, if applicable).

Answer 1

Given that

A varies inversely as the square root of x

Hence,

A  =  k / (√x) ----------> (1)

Substitute x = 15 and A = 45 in Eq (1)

45  =  k / (√15)

k  =  45√15

Substitute x = 30 and k  =  45√15 in Eq (1)

A  =  [ 45√15 ] / √30

A  =  [ 45√(15/30) ]

A  =  [ 45√(1/2) ]

A  =  [ 45/√2 ]

A  =  31.8

Answer :

The value of A is 31.8.