Subtract 81/21 from 42/3
1st number: 14 0/3, 2nd number: 3 18/21
42/3 - 81/21 is 71/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 3 and 21 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 3 × 7 = 21,
42/3 = 42 × 7/3 × 7 = 294/21 - Likewise, for the 2nd fraction, since 21 × 1 = 21,
81/21 = 81 × 1/21 × 1 = 81/21 - Subtract the two like fractions:
294/21 - 81/21 = 294 - 81/21 = 213/21 - After reducing the fraction, the answer is 71/7
- In mixed form: 101/7
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