Add 42/15 and 21/12
1st number: 2 12/15, 2nd number: 1 9/12
42/15 + 21/12 is 91/20.
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,
42/15 = 42 × 4/15 × 4 = 168/60 - Likewise, for the 2nd fraction, since 12 × 5 = 60,
21/12 = 21 × 5/12 × 5 = 105/60 - Add the two like fractions:
168/60 + 105/60 = 168 + 105/60 = 273/60 - 273/60 simplified gives 91/20
- So, 42/15 + 21/12 = 91/20
In mixed form: 411/20
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