Add 21/4 and 18/15
1st number: 5 1/4, 2nd number: 1 3/15
21/4 + 18/15 is 129/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 15 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 4 × 15 = 60,
21/4 = 21 × 15/4 × 15 = 315/60 - Likewise, for the 2nd fraction, since 15 × 4 = 60,
18/15 = 18 × 4/15 × 4 = 72/60 - Add the two like fractions:
315/60 + 72/60 = 315 + 72/60 = 387/60 - 387/60 simplified gives 129/20
- So, 21/4 + 18/15 = 129/20
In mixed form: 69/20
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