Subtract 90/70 from 21/25
1st number: 21/25, 2nd number: 1 20/70
21/25 - 90/70 is -78/175.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 25 and 70 is 350
Next, find the equivalent fraction of both fractional numbers with denominator 350 - For the 1st fraction, since 25 × 14 = 350,
21/25 = 21 × 14/25 × 14 = 294/350 - Likewise, for the 2nd fraction, since 70 × 5 = 350,
90/70 = 90 × 5/70 × 5 = 450/350 - Subtract the two like fractions:
294/350 - 450/350 = 294 - 450/350 = -156/350 - After reducing the fraction, the answer is -78/175
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