Add 15/18 and 21/8
1st number: 15/18, 2nd number: 2 5/8
15/18 + 21/8 is 83/24.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 8 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 18 × 4 = 72,
15/18 = 15 × 4/18 × 4 = 60/72 - Likewise, for the 2nd fraction, since 8 × 9 = 72,
21/8 = 21 × 9/8 × 9 = 189/72 - Add the two like fractions:
60/72 + 189/72 = 60 + 189/72 = 249/72 - 249/72 simplified gives 83/24
- So, 15/18 + 21/8 = 83/24
In mixed form: 311/24
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