Subtract 70/84 from 42/90
42/90 - 70/84 is -11/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 84 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 90 × 14 = 1260,
42/90 = 42 × 14/90 × 14 = 588/1260 - Likewise, for the 2nd fraction, since 84 × 15 = 1260,
70/84 = 70 × 15/84 × 15 = 1050/1260 - Subtract the two like fractions:
588/1260 - 1050/1260 = 588 - 1050/1260 = -462/1260 - After reducing the fraction, the answer is -11/30
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Related: 84/90-70/84