Subtract 10/40 from 81/42
1st number: 1 39/42, 2nd number: 10/40
81/42 - 10/40 is 47/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 42 × 20 = 840,
81/42 = 81 × 20/42 × 20 = 1620/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
10/40 = 10 × 21/40 × 21 = 210/840 - Subtract the two like fractions:
1620/840 - 210/840 = 1620 - 210/840 = 1410/840 - After reducing the fraction, the answer is 47/28
- In mixed form: 119/28
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