Add 21/12 and 70/40
1st number: 1 9/12, 2nd number: 1 30/40
21/12 + 70/40 is 7/2.
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,
70/40 = 70 × 3/40 × 3 = 210/120 - Add the two like fractions:
210/120 + 210/120 = 210 + 210/120 = 420/120 - 420/120 simplified gives 7/2
- So, 21/12 + 70/40 = 7/2
In mixed form: 31/2
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