Subtract 5/70 from 81/42
1st number: 1 39/42, 2nd number: 5/70
81/42 - 5/70 is 13/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 70 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
81/42 = 81 × 5/42 × 5 = 405/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
5/70 = 5 × 3/70 × 3 = 15/210 - Subtract the two like fractions:
405/210 - 15/210 = 405 - 15/210 = 390/210 - After reducing the fraction, the answer is 13/7
- In mixed form: 16/7
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