Subtract 70/90 from 21/84
21/84 - 70/90 is -19/36.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 90 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 84 × 15 = 1260,
21/84 = 21 × 15/84 × 15 = 315/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
70/90 = 70 × 14/90 × 14 = 980/1260 - Subtract the two like fractions:
315/1260 - 980/1260 = 315 - 980/1260 = -665/1260 - After reducing the fraction, the answer is -19/36
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