Add 20/84 and 21/15
1st number: 20/84, 2nd number: 1 6/15
20/84 + 21/15 is 172/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 15 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
20/84 = 20 × 5/84 × 5 = 100/420 - Likewise, for the 2nd fraction, since 15 × 28 = 420,
21/15 = 21 × 28/15 × 28 = 588/420 - Add the two like fractions:
100/420 + 588/420 = 100 + 588/420 = 688/420 - 688/420 simplified gives 172/105
- So, 20/84 + 21/15 = 172/105
In mixed form: 167/105
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