PSLE
Shiyun baked some puffs. She gave ¹₈ of the puffs to her relatives and 48 to her friends. She was left with ¹₂ of the puffs. She packed these into 12 boxes. Some boxes contained 4 puffs while the rest contained 6 puffs.

1. How many puffs were packed into the 12 boxes?
2. How many boxes contained 6 puffs?

(a)
Fraction of the puffs given to her friends
= 1 - ¹₈ - ¹₂

= 1 - ¹₈ - ⁴₈
= ³₈

Number of puffs that Shiyun gave to her friends = 3 u

3 u = 48

1 u = 48 ÷ 3 = 16

Number of puffs that were packed in 12 boxes
= 4 u
= 4 x 16
= 64

Number of puffs that were packed in 12 boxes = 64

Boxes of 6	Puffs	Boxes of 4	Puffs	Total puffs
12	72	0	0	72
11	66	1	4	70

If all the puffs are packed in boxes of 6, the number of puffs needed
= 12 x 6
= 72

Small difference
= 72 - 70
= 2

Big difference
= 72 - 64
= 8

Number of boxes of 4 puffs 
= 8 ÷ 2
= 4

Number of boxes of 6 puffs
= 12 - 4
= 8

Answer(s): (a) 64; (b) 8