Subtract 5/72 from 18/21
18/21 - 5/72 is 397/504.
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,
18/21 = 18 × 24/21 × 24 = 432/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
5/72 = 5 × 7/72 × 7 = 35/504 - Subtract the two like fractions:
432/504 - 35/504 = 432 - 35/504 = 397/504
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