Add 28/15 and 21/18
1st number: 1 13/15, 2nd number: 1 3/18
28/15 + 21/18 is 91/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 15 × 6 = 90,
28/15 = 28 × 6/15 × 6 = 168/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
21/18 = 21 × 5/18 × 5 = 105/90 - Add the two like fractions:
168/90 + 105/90 = 168 + 105/90 = 273/90 - 273/90 simplified gives 91/30
- So, 28/15 + 21/18 = 91/30
In mixed form: 31/30
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