PSLE
Esther baked some muffins. She gave ¹₈ of the muffins to her friends and 145 to her relatives. She was left with ¹₄ of the muffins. She packed these into 10 boxes. Some boxes contained 4 muffins while the rest contained 7 muffins.

1. How many muffins were packed into the 10 boxes?
2. How many boxes contained 7 muffins?

(a)
Fraction of the muffins given to her relatives
= 1 - ¹₈ - ¹₄

= 1 - ¹₈ - ²₈
= ⁵₈

Number of muffins that Esther gave to her relatives = 5 u

5 u = 145

1 u = 145 ÷ 5 = 29

Number of muffins that were packed in 10 boxes
= 2 u
= 2 x 29
= 58

Number of muffins that were packed in 10 boxes = 58

Boxes of 7	Muffins	Boxes of 4	Muffins	Total muffins
10	70	0	0	70
9	63	1	4	67

If all the muffins are packed in boxes of 7, the number of muffins needed
= 10 x 7
= 70

Small difference
= 70 - 67
= 3

Big difference
= 70 - 58
= 12

Number of boxes of 4 muffins 
= 12 ÷ 3
= 4

Number of boxes of 7 muffins
= 10 - 4
= 6

Answer(s): (a) 58; (b) 6