PSLE
Risa and Olivia folded paper stars over two days. On Saturday, Risa folded 22 paper stars more than Olivia. On Sunday, Risa folded another 19 paper stars and Olivia folded another 1. At the end of the two days, Risa made ⁷₉ of the total number of stars. What was the number of paper stars that Olivia folded?

	Risa	Olivia	Difference
Before	1 u + 22	1 u	22
Change	+ 19	+ 1
After	1 u + 41	1 u + 1	40
Comparing between Risa and Olivia in the end	7 p	2 p	5 p

Difference between the number of paper stars that Risa and Olivia folded in the end is repeated.

Difference between the number of paper stars that Risa and Olivia folded in the end
= 7 p - 2 p
= 5 p

Difference between the number of paper stars that Risa and Olivia folded in the end
= (1 u + 41) - (1 u + 1)
= 1 u + 41 - 1 u - 1
= 41 - 1
= 40

5 p = 40

1 p = 40 ÷ 5 = 8

Number of paper stars that Olivia folded
= 2 p
= 2 x 8
= 16

Answer(s): 16