Subtract 45/7 from 21/72
1st number: 21/72, 2nd number: 6 3/7
21/72 - 45/7 is -1031/168.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 7 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
21/72 = 21 × 7/72 × 7 = 147/504 - Likewise, for the 2nd fraction, since 7 × 72 = 504,
45/7 = 45 × 72/7 × 72 = 3240/504 - Subtract the two like fractions:
147/504 - 3240/504 = 147 - 3240/504 = -3093/504 - After reducing the fraction, the answer is -1031/168
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