Subtract 90/70 from 21/75
1st number: 21/75, 2nd number: 1 20/70
21/75 - 90/70 is -176/175.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 75 and 70 is 1050
Next, find the equivalent fraction of both fractional numbers with denominator 1050 - For the 1st fraction, since 75 × 14 = 1050,
21/75 = 21 × 14/75 × 14 = 294/1050 - Likewise, for the 2nd fraction, since 70 × 15 = 1050,
90/70 = 90 × 15/70 × 15 = 1350/1050 - Subtract the two like fractions:
294/1050 - 1350/1050 = 294 - 1350/1050 = -1056/1050 - After reducing the fraction, the answer is -176/175
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