Add 21/12 and 9/40
1st number: 1 9/12, 2nd number: 9/40
21/12 + 9/40 is 79/40.
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,
21/12 = 21 × 10/12 × 10 = 210/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
9/40 = 9 × 3/40 × 3 = 27/120 - Add the two like fractions:
210/120 + 27/120 = 210 + 27/120 = 237/120 - 237/120 simplified gives 79/40
- So, 21/12 + 9/40 = 79/40
In mixed form: 139/40
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