Subtract 70/21 from 84/20
1st number: 4 4/20, 2nd number: 3 7/21
84/20 - 70/21 is 13/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
84/20 = 84 × 21/20 × 21 = 1764/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
70/21 = 70 × 20/21 × 20 = 1400/420 - Subtract the two like fractions:
1764/420 - 1400/420 = 1764 - 1400/420 = 364/420 - After reducing the fraction, the answer is 13/15
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