PSLE
Emily and Ivory folded paper balls over two days. On Thursday, Emily folded 76 paper balls more than Ivory. On Friday, Emily folded another 12 paper balls and Ivory folded another 18. At the end of the two days, Emily made ⁷₉ of the total number of balls. What was the number of paper balls that Ivory folded?

	Emily	Ivory	Difference
Before	1 u + 76	1 u	76
Change	+ 12	+ 18
After	1 u + 88	1 u + 18	70
Comparing between Emily and Ivory in the end	7 p	2 p	5 p

Difference between the number of paper balls that Emily and Ivory folded in the end is repeated.

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

Difference between the number of paper balls that Emily and Ivory folded in the end
= (1 u + 88) - (1 u + 18)
= 1 u + 88 - 1 u - 18
= 88 - 18
= 70

5 p = 70

1 p = 70 ÷ 5 = 14

Number of paper balls that Ivory folded
= 2 p
= 2 x 14
= 28

Answer(s): 28