Add 21/12 and 15/40
1st number: 1 9/12, 2nd number: 15/40
21/12 + 15/40 is 17/8.
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,
21/12 = 21 × 10/12 × 10 = 210/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
15/40 = 15 × 3/40 × 3 = 45/120 - Add the two like fractions:
210/120 + 45/120 = 210 + 45/120 = 255/120 - 255/120 simplified gives 17/8
- So, 21/12 + 15/40 = 17/8
In mixed form: 21/8
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