Add 21/15 and 45/12
1st number: 1 6/15, 2nd number: 3 9/12
21/15 + 45/12 is 103/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 12 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 15 × 4 = 60,
21/15 = 21 × 4/15 × 4 = 84/60 - Likewise, for the 2nd fraction, since 12 × 5 = 60,
45/12 = 45 × 5/12 × 5 = 225/60 - Add the two like fractions:
84/60 + 225/60 = 84 + 225/60 = 309/60 - 309/60 simplified gives 103/20
- So, 21/15 + 45/12 = 103/20
In mixed form: 53/20
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