Subtract 45/70 from 21/84
21/84 - 45/70 is -11/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 70 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Likewise, for the 2nd fraction, since 70 × 6 = 420,
45/70 = 45 × 6/70 × 6 = 270/420 - Subtract the two like fractions:
105/420 - 270/420 = 105 - 270/420 = -165/420 - After reducing the fraction, the answer is -11/28
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