PSLE
Shiyun and Jane folded paper stars over two days. On Tuesday, Shiyun folded 7 paper stars more than Jane. On Wednesday, Shiyun folded another 12 paper stars and Jane folded another 1. At the end of the two days, Shiyun made ⁵₇ of the total number of stars. What was the number of paper stars that Shiyun folded?

	Shiyun	Jane	Difference
Before	1 u + 7	1 u	7
Change	+ 12	+ 1
After	1 u + 19	1 u + 1	18
Comparing between Shiyun and Jane in the end	5 p	2 p	3 p

Difference between the number of paper stars that Shiyun and Jane folded in the end is repeated.

Difference between the number of paper stars that Shiyun and Jane folded in the end
= 5 p - 2 p
= 3 p

Difference between the number of paper stars that Shiyun and Jane folded in the end
= (1 u + 19) - (1 u + 1)
= 1 u + 19 - 1 u - 1
= 19 - 1
= 18

3 p = 18

1 p = 18 ÷ 3 = 6

Number of paper stars that Shiyun folded
= 5 p
= 5 x 6
= 30

Answer(s): 30