PSLE
Ivory and Gabriel bought jigsaw puzzles at the prices shown below.

2 Large jigsaw puzzles for $9
5 Small jigsaw puzzles for $6

1. Ivory bought an equal number of large and small jigsaw puzzles. She spent $132 more on the large ones. How many jigsaw puzzles did she buy altogether?
2. Gabriel spent an equal amount of money on the large and small jigsaw puzzles. What fraction of the jigsaw puzzles he bought were small?

(a)
Number of large and small jigsaw puzzles that Ivory bought is the same. Make the number of large and small jigsaw puzzles the same. LCM of 2 and 5 is 10.

Cost of 2 large jigsaw puzzles = $9
Cost of 10 large jigsaw puzzles = 5 x 9 = $45

Cost of 5 small jigsaw puzzles = $6
Cost of 10 small jigsaw puzzles = 2 x 6 = $12

Difference in the cost of buying 10 small jigsaw puzzles and 10 large jigsaw puzzles
= 45 - 12
= $33

Number of sets of jigsaw puzzles
= 132 ÷ 33
= 4

Number of jigsaw puzzles that Ivory bought
= 4 x 2 x 10
= 80

(b)
Gabriel spent an equal amount of money on the large and small jigsaw puzzles. Make the amount of money spent on the large and small jigsaw puzzles the same.
LCM of 9 and 6 is 18.

Number of large jigsaw puzzles that Gabriel bought
= 2 x (18 ÷ 9)
= 2 x 2
= 4

Number of the small jigsaw puzzles that Gabriel bought
= 5 x (18 ÷ 6)
= 5 x 3
= 15

Fraction of the jigsaw puzzles that Gabriel bought that were small
= ¹⁵_{4 + 15}
= ¹⁵₁₉

Answer(s): (a) 80; (b) ¹⁵₁₉