Question

m is directly proportional to r^3
when r=4, m=160
what is the value of m when r=2

Answer 1

Answer:

If m is directly proportional to r then when r doubled m also doubled,

ris 4 and mis 160

when r is 2 then m= 80

Answer 2

Answer:

M=20

Step-by-step explanation:

M = (k) r³

160 = (k) 4³

160 = k x 64

160 ÷ 64 = 2.5

M = 2.5 x (2)³

M = 2.5 x 8

M = 20