Add 21/84 and 15/5
1st number: 21/84, 2nd number: 3 0/5
21/84 + 15/5 is 13/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 5 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 5 × 84 = 420,
15/5 = 15 × 84/5 × 84 = 1260/420 - Add the two like fractions:
105/420 + 1260/420 = 105 + 1260/420 = 1365/420 - 1365/420 simplified gives 13/4
- So, 21/84 + 15/5 = 13/4
In mixed form: 31/4
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