At a bakery, there were equal numbers of muffins, scones and cookies at first. After 12 muffins were sold, some scones and cookies were also sold. Then there were 81 pastries left. There were 3 times as many muffins left as scones. The number of cookies left was 6 more than the number of scones left. How many muffins were there at first?
- 45
- 57
- 63
- 69
Need a hint?
Work out the number left for each type first, then add back the 12 muffins that were sold.
Worked answer
- Let the number of scones left be s.
- Then cookies left = s + 6 and muffins left = 3s.
- Total left: 3s + s + (s + 6) = 81, so 5s + 6 = 81.
- 5s = 75, so s = 15 scones left.
- Muffins left = 3 × 15 = 45.
- Muffins at first = 45 + 12 = 57.
- Answer: 57.
Answer: 57
The mistake this question tests
Habit
Calculation slip
Pupils often stop at the 45 muffins left and forget to add back the 12 muffins that were sold.
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