Add 18/28 and 21/15
1st number: 18/28, 2nd number: 1 6/15
18/28 + 21/15 is 143/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 15 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 28 × 15 = 420,
18/28 = 18 × 15/28 × 15 = 270/420 - Likewise, for the 2nd fraction, since 15 × 28 = 420,
21/15 = 21 × 28/15 × 28 = 588/420 - Add the two like fractions:
270/420 + 588/420 = 270 + 588/420 = 858/420 - 858/420 simplified gives 143/70
- So, 18/28 + 21/15 = 143/70
In mixed form: 23/70
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