Subtract 40/30 from 81/63
1st number: 1 18/63, 2nd number: 1 10/30
81/63 - 40/30 is -1/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 30 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 63 × 10 = 630,
81/63 = 81 × 10/63 × 10 = 810/630 - Likewise, for the 2nd fraction, since 30 × 21 = 630,
40/30 = 40 × 21/30 × 21 = 840/630 - Subtract the two like fractions:
810/630 - 840/630 = 810 - 840/630 = -30/630 - After reducing the fraction, the answer is -1/21
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