Add 15/12 and 21/20
1st number: 1 3/12, 2nd number: 1 1/20
15/12 + 21/20 is 23/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 20 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 12 × 5 = 60,
15/12 = 15 × 5/12 × 5 = 75/60 - Likewise, for the 2nd fraction, since 20 × 3 = 60,
21/20 = 21 × 3/20 × 3 = 63/60 - Add the two like fractions:
75/60 + 63/60 = 75 + 63/60 = 138/60 - 138/60 simplified gives 23/10
- So, 15/12 + 21/20 = 23/10
In mixed form: 23/10
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