Subtract 40/70 from 81/42
1st number: 1 39/42, 2nd number: 40/70
81/42 - 40/70 is 19/14.
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,
40/70 = 40 × 3/70 × 3 = 120/210 - Subtract the two like fractions:
405/210 - 120/210 = 405 - 120/210 = 285/210 - After reducing the fraction, the answer is 19/14
- In mixed form: 15/14
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