Subtract 9/24 from 15/21, Solve 15/21

Subtract 9/24 from 15/21

15/21 - 9/24 is 19/56.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 24 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 21 × 8 = 168,
15/21 = 15 × 8/21 × 8 = 120/168
Likewise, for the 2nd fraction, since 24 × 7 = 168,
9/24 = 9 × 7/24 × 7 = 63/168
Subtract the two like fractions:
120/168 - 63/168 = 120 - 63/168 = 57/168
After reducing the fraction, the answer is 19/56

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