Add 21/40 and 70/30
1st number: 21/40, 2nd number: 2 10/30
21/40 + 70/30 is 343/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 30 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 40 × 3 = 120,
21/40 = 21 × 3/40 × 3 = 63/120 - Likewise, for the 2nd fraction, since 30 × 4 = 120,
70/30 = 70 × 4/30 × 4 = 280/120 - Add the two like fractions:
63/120 + 280/120 = 63 + 280/120 = 343/120 - So, 21/40 + 70/30 = 343/120
In mixed form: 2103/120
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