Add 15/12 and 21/40
1st number: 1 3/12, 2nd number: 21/40
15/12 + 21/40 is 71/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 12 × 10 = 120,
15/12 = 15 × 10/12 × 10 = 150/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
21/40 = 21 × 3/40 × 3 = 63/120 - Add the two like fractions:
150/120 + 63/120 = 150 + 63/120 = 213/120 - 213/120 simplified gives 71/40
- So, 15/12 + 21/40 = 71/40
In mixed form: 131/40
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