Subtract 81/63 from 18/40
1st number: 18/40, 2nd number: 1 18/63
18/40 - 81/63 is -117/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 63 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 40 × 63 = 2520,
18/40 = 18 × 63/40 × 63 = 1134/2520 - Likewise, for the 2nd fraction, since 63 × 40 = 2520,
81/63 = 81 × 40/63 × 40 = 3240/2520 - Subtract the two like fractions:
1134/2520 - 3240/2520 = 1134 - 3240/2520 = -2106/2520 - After reducing the fraction, the answer is -117/140
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