Subtract 84/63 from 72/90
1st number: 72/90, 2nd number: 1 21/63
72/90 - 84/63 is -8/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 63 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 63 × 10 = 630,
84/63 = 84 × 10/63 × 10 = 840/630 - Subtract the two like fractions:
504/630 - 840/630 = 504 - 840/630 = -336/630 - After reducing the fraction, the answer is -8/15
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