PSLE
Dana and Betty folded paper stars over two days. On Monday, Dana folded 35 paper stars more than Betty. On Tuesday, Dana folded another 17 paper stars and Betty folded another 7. At the end of the two days, Dana made ⁵₇ of the total number of stars. What was the number of paper stars that Dana folded?

	Dana	Betty	Difference
Before	1 u + 35	1 u	35
Change	+ 17	+ 7
After	1 u + 52	1 u + 7	45
Comparing between Dana and Betty in the end	5 p	2 p	3 p

Difference between the number of paper stars that Dana and Betty folded in the end is repeated.

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

Difference between the number of paper stars that Dana and Betty folded in the end
= (1 u + 52) - (1 u + 7)
= 1 u + 52 - 1 u - 7
= 52 - 7
= 45

3 p = 45

1 p = 45 ÷ 3 = 15

Number of paper stars that Dana folded
= 5 p
= 5 x 15
= 75

Answer(s): 75