Subtract 80/90 from 7/28
7/28 - 80/90 is -23/36.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 90 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 28 × 45 = 1260,
7/28 = 7 × 45/28 × 45 = 315/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
80/90 = 80 × 14/90 × 14 = 1120/1260 - Subtract the two like fractions:
315/1260 - 1120/1260 = 315 - 1120/1260 = -805/1260 - After reducing the fraction, the answer is -23/36
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