Subtract 84/90 from 28/70
28/70 - 84/90 is -8/15.
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,
84/90 = 84 × 7/90 × 7 = 588/630 - Subtract the two like fractions:
252/630 - 588/630 = 252 - 588/630 = -336/630 - After reducing the fraction, the answer is -8/15
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