Subtract 21/72 from 90/84
1st number: 1 6/84, 2nd number: 21/72
90/84 - 21/72 is 131/168.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 84 × 6 = 504,
90/84 = 90 × 6/84 × 6 = 540/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
21/72 = 21 × 7/72 × 7 = 147/504 - Subtract the two like fractions:
540/504 - 147/504 = 540 - 147/504 = 393/504 - After reducing the fraction, the answer is 131/168
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