Subtract 81/7 from 45/20
1st number: 2 5/20, 2nd number: 11 4/7
45/20 - 81/7 is -261/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 7 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 20 × 7 = 140,
45/20 = 45 × 7/20 × 7 = 315/140 - Likewise, for the 2nd fraction, since 7 × 20 = 140,
81/7 = 81 × 20/7 × 20 = 1620/140 - Subtract the two like fractions:
315/140 - 1620/140 = 315 - 1620/140 = -1305/140 - After reducing the fraction, the answer is -261/28
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