Subtract 70/7 from 90/20
1st number: 4 10/20, 2nd number: 10 0/7
90/20 - 70/7 is -11/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 7 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 20 × 7 = 140,
90/20 = 90 × 7/20 × 7 = 630/140 - Likewise, for the 2nd fraction, since 7 × 20 = 140,
70/7 = 70 × 20/7 × 20 = 1400/140 - Subtract the two like fractions:
630/140 - 1400/140 = 630 - 1400/140 = -770/140 - After reducing the fraction, the answer is -11/2
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