Question

5/9 of a piece of metal has a mass of 7 kg. What is the mass of 2/7 of the metal?

Answer 1

5/9 of a piece of metal has a mass 7kg
1 of a piece of metal has a mass =7/(5/9)
=63/5kg
hence 2/7 of a piece of metal has a mass
=63/5x2/7=18/5kg=3.6 kg

Answer 2

Let the mass of metal is x kg , then;
(5/9) of x = 7
5x/9 = 7
5x = 63
x = (63/5)

(2/7) of x
= (2/7)×(63/5)
= 126/35
= 3.6

hence 2/7 of a metal piece had 3.6 kg mass