Subtract 25/72 from 4/21
4/21 - 25/72 is -79/504.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 21 × 24 = 504,
4/21 = 4 × 24/21 × 24 = 96/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
25/72 = 25 × 7/72 × 7 = 175/504 - Subtract the two like fractions:
96/504 - 175/504 = 96 - 175/504 = -79/504
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