15 pastries and 12 biscuit packets have been donated for a school fete. These are to be packed in several smaller identical boxes with the same number of pastries and biscuit packets in each. How many biscuit packets and how many pastries will each box contain?
To find the number of biscuit packets and pastries, we should find HCF of 15 and 12
Prime factors of 15 = 3 × 5
Prime factors of 12 = 2 × 2 × 3
Therefore HCF of 15 and 12 is: 3
Number of pastries = 
= 5
Number of biscuit packets = 
= 4
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