Subtract 30/84 from 21/70
21/70 - 30/84 is -2/35.
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,
21/70 = 21 × 6/70 × 6 = 126/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
30/84 = 30 × 5/84 × 5 = 150/420 - Subtract the two like fractions:
126/420 - 150/420 = 126 - 150/420 = -24/420 - After reducing the fraction, the answer is -2/35
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