Subtract 21/72 from 1/7
1/7 - 21/72 is -25/168.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 7 × 72 = 504,
1/7 = 1 × 72/7 × 72 = 72/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
21/72 = 21 × 7/72 × 7 = 147/504 - Subtract the two like fractions:
72/504 - 147/504 = 72 - 147/504 = -75/504 - After reducing the fraction, the answer is -25/168
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