Subtract 4/72 from 21/70
21/70 - 4/72 is 11/45.
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,
21/70 = 21 × 36/70 × 36 = 756/2520 - Likewise, for the 2nd fraction, since 72 × 35 = 2520,
4/72 = 4 × 35/72 × 35 = 140/2520 - Subtract the two like fractions:
756/2520 - 140/2520 = 756 - 140/2520 = 616/2520 - After reducing the fraction, the answer is 11/45
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