Subtract 21/84 from 4/5
4/5 - 21/84 is 11/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 5 × 84 = 420,
4/5 = 4 × 84/5 × 84 = 336/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Subtract the two like fractions:
336/420 - 105/420 = 336 - 105/420 = 231/420 - After reducing the fraction, the answer is 11/20
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