Subtract 1/72 from 21/70
21/70 - 1/72 is 103/360.
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,
1/72 = 1 × 35/72 × 35 = 35/2520 - Subtract the two like fractions:
756/2520 - 35/2520 = 756 - 35/2520 = 721/2520 - After reducing the fraction, the answer is 103/360
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