PSLE
Gem and Elyse folded paper balls over two days. On Wednesday, Gem folded 39 paper balls more than Elyse. On Thursday, Gem folded another 28 paper balls and Elyse folded another 2. At the end of the two days, Gem made ⁷₉ of the total number of balls. What was the number of paper balls that Gem folded?

	Gem	Elyse	Difference
Before	1 u + 39	1 u	39
Change	+ 28	+ 2
After	1 u + 67	1 u + 2	65
Comparing between Gem and Elyse in the end	7 p	2 p	5 p

Difference between the number of paper balls that Gem and Elyse folded in the end is repeated.

Difference between the number of paper balls that Gem and Elyse folded in the end
= 7 p - 2 p
= 5 p

Difference between the number of paper balls that Gem and Elyse folded in the end
= (1 u + 67) - (1 u + 2)
= 1 u + 67 - 1 u - 2
= 67 - 2
= 65

5 p = 65

1 p = 65 ÷ 5 = 13

Number of paper balls that Gem folded
= 7 p
= 7 x 13
= 91

Answer(s): 91