Subtract 15/24 from 21/84
21/84 - 15/24 is -3/8.
Steps for subtracting fractions
- 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,
15/24 = 15 × 7/24 × 7 = 105/168 - Subtract the two like fractions:
42/168 - 105/168 = 42 - 105/168 = -63/168 - After reducing the fraction, the answer is -3/8
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