Question

T is directly proportional to M.

Answer 1

a) T when M=3

T = 15

 b) M when T=10

M = 2

Answer 2

By proportionality, for any number $a$, if T is multiplied by $a$ then the same goes for M.

a) M has been multiplied by $\dfrac{3}4$ hence $T=20\cdot\dfrac{3}4=5\cdot3=15$

$\boxed{T=15}$

b) T has been divided by $2$ hence $M=\dfrac{4}2$

$\boxed{M=2}$