Subtract 3/72 from 21/28
21/28 - 3/72 is 17/24.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 28 × 18 = 504,
21/28 = 21 × 18/28 × 18 = 378/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
3/72 = 3 × 7/72 × 7 = 21/504 - Subtract the two like fractions:
378/504 - 21/504 = 378 - 21/504 = 357/504 - After reducing the fraction, the answer is 17/24
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