PSLE
Anna baked some puffs. She gave ¹₅ of the puffs to her relatives and 132 to her friends. She was left with ¹₂ of the puffs. She packed these into 20 boxes. Some boxes contained 8 puffs while the rest contained 13 puffs.

1. How many puffs were packed into the 20 boxes?
2. How many boxes contained 13 puffs?

(a)
Fraction of the puffs given to her friends
= 1 - ¹₅ - ¹₂

= 1 - ²₁₀ - ⁵₁₀
= ³₁₀

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

3 u = 132

1 u = 132 ÷ 3 = 44

Number of puffs that were packed in 20 boxes
= 5 u
= 5 x 44
= 220

Number of puffs that were packed in 20 boxes = 220

Boxes of 13	Puffs	Boxes of 8	Puffs	Total puffs
20	260	0	0	260
19	247	1	8	255

If all the puffs are packed in boxes of 13, the number of puffs needed
= 20 x 13
= 260

Small difference
= 260 - 255
= 5

Big difference
= 260 - 220
= 40

Number of boxes of 8 puffs 
= 40 ÷ 5
= 8

Number of boxes of 13 puffs
= 20 - 8
= 12

Answer(s): (a) 220; (b) 12