Subtract 90/20 from 28/7
1st number: 4 0/7, 2nd number: 4 10/20
28/7 - 90/20 is -1/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 7 × 20 = 140,
28/7 = 28 × 20/7 × 20 = 560/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
90/20 = 90 × 7/20 × 7 = 630/140 - Subtract the two like fractions:
560/140 - 630/140 = 560 - 630/140 = -70/140 - After reducing the fraction, the answer is -1/2
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