PSLE
Kimberly baked some muffins. She gave ¹₅ of the muffins to her friends and 66 to her students. She was left with ¹₂ of the muffins. She packed these into 12 boxes. Some boxes contained 8 muffins while the rest contained 10 muffins.

1. How many muffins were packed into the 12 boxes?
2. How many boxes contained 10 muffins?

(a)
Fraction of the muffins given to her students
= 1 - ¹₅ - ¹₂

= 1 - ²₁₀ - ⁵₁₀
= ³₁₀

Number of muffins that Kimberly gave to her students = 3 u

3 u = 66

1 u = 66 ÷ 3 = 22

Number of muffins that were packed in 12 boxes
= 5 u
= 5 x 22
= 110

Number of muffins that were packed in 12 boxes = 110

Boxes of 10	Muffins	Boxes of 8	Muffins	Total muffins
12	120	0	0	120
11	110	1	8	118

If all the muffins are packed in boxes of 10, the number of muffins needed
= 12 x 10
= 120

Small difference
= 120 - 118
= 2

Big difference
= 120 - 110
= 10

Number of boxes of 8 muffins 
= 10 ÷ 2
= 5

Number of boxes of 10 muffins
= 12 - 5
= 7

Answer(s): (a) 110; (b) 7