Add 72/40 and 21/12
1st number: 1 32/40, 2nd number: 1 9/12
72/40 + 21/12 is 71/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 12 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 40 × 3 = 120,
72/40 = 72 × 3/40 × 3 = 216/120 - Likewise, for the 2nd fraction, since 12 × 10 = 120,
21/12 = 21 × 10/12 × 10 = 210/120 - Add the two like fractions:
216/120 + 210/120 = 216 + 210/120 = 426/120 - 426/120 simplified gives 71/20
- So, 72/40 + 21/12 = 71/20
In mixed form: 311/20
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