Subtract 18/21 from 1/72
1/72 - 18/21 is -425/504.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 21 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
1/72 = 1 × 7/72 × 7 = 7/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
18/21 = 18 × 24/21 × 24 = 432/504 - Subtract the two like fractions:
7/504 - 432/504 = 7 - 432/504 = -425/504
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