Subtract 81/40 from 72/49
1st number: 1 23/49, 2nd number: 2 1/40
72/49 - 81/40 is -1089/1960.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 49 and 40 is 1960
Next, find the equivalent fraction of both fractional numbers with denominator 1960 - For the 1st fraction, since 49 × 40 = 1960,
72/49 = 72 × 40/49 × 40 = 2880/1960 - Likewise, for the 2nd fraction, since 40 × 49 = 1960,
81/40 = 81 × 49/40 × 49 = 3969/1960 - Subtract the two like fractions:
2880/1960 - 3969/1960 = 2880 - 3969/1960 = -1089/1960
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