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# A person has four iron bars whose lengths are 24 m, 36 m, 48 m and 72 m respectively. This person wants to cut pieces of same length from each of four bars. What is the least number of total pieces if he is to cut without any wastage?

[ A ]    10
[ B ]    15
[ C ]    20
[ D ]    25
 Answer : Option B Explanation : 24 = 12 $\times$ 2, 36 = 12 $\times$ 3, 48 = 12 $\times$ 4, and 72 = 12 $\times$ 6 HCF (24, 36, 48, 72) = 12 Total pieces = 2 + 3 + 4 + 6 = 15