Subtract 70/21 from 90/56
1st number: 1 34/56, 2nd number: 3 7/21
90/56 - 70/21 is -145/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 56 × 3 = 168,
90/56 = 90 × 3/56 × 3 = 270/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
70/21 = 70 × 8/21 × 8 = 560/168 - Subtract the two like fractions:
270/168 - 560/168 = 270 - 560/168 = -290/168 - After reducing the fraction, the answer is -145/84
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