PSLE
Zara and Julie folded paper stars over two days. On Monday, Zara folded 7 paper stars more than Julie. On Tuesday, Zara folded another 21 paper stars and Julie folded another 10. At the end of the two days, Zara made ⁵₈ of the total number of stars. What was the number of paper stars that Zara folded?

	Zara	Julie	Difference
Before	1 u + 7	1 u	7
Change	+ 21	+ 10
After	1 u + 28	1 u + 10	18
Comparing between Zara and Julie in the end	5 p	3 p	2 p

Difference between the number of paper stars that Zara and Julie folded in the end is repeated.

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

Difference between the number of paper stars that Zara and Julie folded in the end
= (1 u + 28) - (1 u + 10)
= 1 u + 28 - 1 u - 10
= 28 - 10
= 18

2 p = 18

1 p = 18 ÷ 2 = 9

Number of paper stars that Zara folded
= 5 p
= 5 x 9
= 45

Answer(s): 45