Add 84/15 and 21/84
1st number: 5 9/15, 2nd number: 21/84
84/15 + 21/84 is 117/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 15 × 28 = 420,
84/15 = 84 × 28/15 × 28 = 2352/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Add the two like fractions:
2352/420 + 105/420 = 2352 + 105/420 = 2457/420 - 2457/420 simplified gives 117/20
- So, 84/15 + 21/84 = 117/20
In mixed form: 517/20
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