Subtract 42/84 from 12/90
12/90 - 42/84 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,
12/90 = 12 × 14/90 × 14 = 168/1260 - Likewise, for the 2nd fraction, since 84 × 15 = 1260,
42/84 = 42 × 15/84 × 15 = 630/1260 - Subtract the two like fractions:
168/1260 - 630/1260 = 168 - 630/1260 = -462/1260 - After reducing the fraction, the answer is -11/30
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