Subtract 3/72 from 21/56
21/56 - 3/72 is 1/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 56 × 9 = 504,
21/56 = 21 × 9/56 × 9 = 189/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
3/72 = 3 × 7/72 × 7 = 21/504 - Subtract the two like fractions:
189/504 - 21/504 = 189 - 21/504 = 168/504 - After reducing the fraction, the answer is 1/3
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