Subtract 70/84 from 30/70
30/70 - 70/84 is -17/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 70 × 6 = 420,
30/70 = 30 × 6/70 × 6 = 180/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
70/84 = 70 × 5/84 × 5 = 350/420 - Subtract the two like fractions:
180/420 - 350/420 = 180 - 350/420 = -170/420 - After reducing the fraction, the answer is -17/42
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