Subtract 30/40 from 12/84
12/84 - 30/40 is -17/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 84 × 10 = 840,
12/84 = 12 × 10/84 × 10 = 120/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
30/40 = 30 × 21/40 × 21 = 630/840 - Subtract the two like fractions:
120/840 - 630/840 = 120 - 630/840 = -510/840 - After reducing the fraction, the answer is -17/28
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