PSLE
Dana and Gwen folded paper balls over two days. On Tuesday, Dana folded 35 paper balls more than Gwen. On Wednesday, Dana folded another 23 paper balls and Gwen folded another 3. At the end of the two days, Dana made ⁷₉ of the total number of balls. What was the number of paper balls that Dana folded?

	Dana	Gwen	Difference
Before	1 u + 35	1 u	35
Change	+ 23	+ 3
After	1 u + 58	1 u + 3	55
Comparing between Dana and Gwen in the end	7 p	2 p	5 p

Difference between the number of paper balls that Dana and Gwen folded in the end is repeated.

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

Difference between the number of paper balls that Dana and Gwen folded in the end
= (1 u + 58) - (1 u + 3)
= 1 u + 58 - 1 u - 3
= 58 - 3
= 55

5 p = 55

1 p = 55 ÷ 5 = 11

Number of paper balls that Dana folded
= 7 p
= 7 x 11
= 77

Answer(s): 77