Subtract 1/72 from 21/63
21/63 - 1/72 is 23/72.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 63 × 8 = 504,
21/63 = 21 × 8/63 × 8 = 168/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
1/72 = 1 × 7/72 × 7 = 7/504 - Subtract the two like fractions:
168/504 - 7/504 = 168 - 7/504 = 161/504 - After reducing the fraction, the answer is 23/72
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