Add 18/15 and 21/84
1st number: 1 3/15, 2nd number: 21/84
18/15 + 21/84 is 29/20.
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,
18/15 = 18 × 28/15 × 28 = 504/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Add the two like fractions:
504/420 + 105/420 = 504 + 105/420 = 609/420 - 609/420 simplified gives 29/20
- So, 18/15 + 21/84 = 29/20
In mixed form: 19/20
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