PSLE
Ivory baked some puffs. She gave ¹₈ of the puffs to her relatives and 126 to her friends. She was left with ¹₂ of the puffs. She packed these into 16 boxes. Some boxes contained 8 puffs while the rest contained 12 puffs.

1. How many puffs were packed into the 16 boxes?
2. How many boxes contained 12 puffs?

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

= 1 - ¹₈ - ⁴₈
= ³₈

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

3 u = 126

1 u = 126 ÷ 3 = 42

Number of puffs that were packed in 16 boxes
= 4 u
= 4 x 42
= 168

Number of puffs that were packed in 16 boxes = 168

Boxes of 12	Puffs	Boxes of 8	Puffs	Total puffs
16	192	0	0	192
15	180	1	8	188

If all the puffs are packed in boxes of 12, the number of puffs needed
= 16 x 12
= 192

Small difference
= 192 - 188
= 4

Big difference
= 192 - 168
= 24

Number of boxes of 8 puffs 
= 24 ÷ 4
= 6

Number of boxes of 12 puffs
= 16 - 6
= 10

Answer(s): (a) 168; (b) 10