Subtract 21/45 from 81/40
1st number: 2 1/40, 2nd number: 21/45
81/40 - 21/45 is 187/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 45 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
81/40 = 81 × 9/40 × 9 = 729/360 - Likewise, for the 2nd fraction, since 45 × 8 = 360,
21/45 = 21 × 8/45 × 8 = 168/360 - Subtract the two like fractions:
729/360 - 168/360 = 729 - 168/360 = 561/360 - After reducing the fraction, the answer is 187/120
- In mixed form: 167/120
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