Subtract 10/15 from 40/84
40/84 - 10/15 is -4/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 15 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
40/84 = 40 × 5/84 × 5 = 200/420 - Likewise, for the 2nd fraction, since 15 × 28 = 420,
10/15 = 10 × 28/15 × 28 = 280/420 - Subtract the two like fractions:
200/420 - 280/420 = 200 - 280/420 = -80/420 - After reducing the fraction, the answer is -4/21
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