Subtract 7/40 from 81/20
1st number: 4 1/20, 2nd number: 7/40
81/20 - 7/40 is 31/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 40 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 20 × 2 = 40,
81/20 = 81 × 2/20 × 2 = 162/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
7/40 = 7 × 1/40 × 1 = 7/40 - Subtract the two like fractions:
162/40 - 7/40 = 162 - 7/40 = 155/40 - After reducing the fraction, the answer is 31/8
- In mixed form: 37/8
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