Subtract 10/24 from 21/84, Solve 21/84

Subtract 10/24 from 21/84

21/84 - 10/24 is -1/6.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 24 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 84 × 2 = 168,
21/84 = 21 × 2/84 × 2 = 42/168
Likewise, for the 2nd fraction, since 24 × 7 = 168,
10/24 = 10 × 7/24 × 7 = 70/168
Subtract the two like fractions:
42/168 - 70/168 = 42 - 70/168 = -28/168
After reducing the fraction, the answer is -1/6

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