Subtract 3/84 from 21/20
1st number: 1 1/20, 2nd number: 3/84
21/20 - 3/84 is 71/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
21/20 = 21 × 21/20 × 21 = 441/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
3/84 = 3 × 5/84 × 5 = 15/420 - Subtract the two like fractions:
441/420 - 15/420 = 441 - 15/420 = 426/420 - After reducing the fraction, the answer is 71/70
- In mixed form: 11/70
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