Subtract 12/72 from 1/21
1/21 - 12/72 is -5/42.
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,
1/21 = 1 × 24/21 × 24 = 24/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
12/72 = 12 × 7/72 × 7 = 84/504 - Subtract the two like fractions:
24/504 - 84/504 = 24 - 84/504 = -60/504 - After reducing the fraction, the answer is -5/42
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