Subtract 56/21 from 72/90
1st number: 72/90, 2nd number: 2 14/21
72/90 - 56/21 is -28/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
72/90 = 72 × 7/90 × 7 = 504/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
56/21 = 56 × 30/21 × 30 = 1680/630 - Subtract the two like fractions:
504/630 - 1680/630 = 504 - 1680/630 = -1176/630 - After reducing the fraction, the answer is -28/15
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