A sack of flour had a mass of 9 kg at first. From the sack of flour, Lily filled some containers with 5/8 kg of flour each.

Question

(a) What was the greatest number of containers she could fill with 5/8 kg of flour each? (b) What was the mass of flour left in the sack?

Answer 1

9/(5/8)

= 9(8/5) (division by a fraction is the same as multiplying by the inverse of the fraction)

=(9x8)/5

72/5

= 14 2/5 containers of 5/8 kg each

14 is the maximum number of containers that can be filled,

with 2/5 container left over which is (2/5)(5/8) = 2/8 = 1/4 kg left over in the sack