Subtract 21/72 from 15/70
15/70 - 21/72 is -13/168.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 72 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 70 × 36 = 2520,
15/70 = 15 × 36/70 × 36 = 540/2520 - Likewise, for the 2nd fraction, since 72 × 35 = 2520,
21/72 = 21 × 35/72 × 35 = 735/2520 - Subtract the two like fractions:
540/2520 - 735/2520 = 540 - 735/2520 = -195/2520 - After reducing the fraction, the answer is -13/168
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