Subtract 49/90 from 28/70
28/70 - 49/90 is -13/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
28/70 = 28 × 9/70 × 9 = 252/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
49/90 = 49 × 7/90 × 7 = 343/630 - Subtract the two like fractions:
252/630 - 343/630 = 252 - 343/630 = -91/630 - After reducing the fraction, the answer is -13/90
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