Subtract 20/7 from 90/40
1st number: 2 10/40, 2nd number: 2 6/7
90/40 - 20/7 is -17/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 7 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 40 × 7 = 280,
90/40 = 90 × 7/40 × 7 = 630/280 - Likewise, for the 2nd fraction, since 7 × 40 = 280,
20/7 = 20 × 40/7 × 40 = 800/280 - Subtract the two like fractions:
630/280 - 800/280 = 630 - 800/280 = -170/280 - After reducing the fraction, the answer is -17/28
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