Subtract 81/40 from 20/5
1st number: 4 0/5, 2nd number: 2 1/40
20/5 - 81/40 is 79/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 40 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 5 × 8 = 40,
20/5 = 20 × 8/5 × 8 = 160/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
81/40 = 81 × 1/40 × 1 = 81/40 - Subtract the two like fractions:
160/40 - 81/40 = 160 - 81/40 = 79/40 - In mixed form: 139/40
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