Subtract 18/7 from 21/72
1st number: 21/72, 2nd number: 2 4/7
21/72 - 18/7 is -383/168.
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,
18/7 = 18 × 72/7 × 72 = 1296/504 - Subtract the two like fractions:
147/504 - 1296/504 = 147 - 1296/504 = -1149/504 - After reducing the fraction, the answer is -383/168
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