Add 21/30 and 15/40
21/30 + 15/40 is 43/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 30 × 4 = 120,
21/30 = 21 × 4/30 × 4 = 84/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
15/40 = 15 × 3/40 × 3 = 45/120 - Add the two like fractions:
84/120 + 45/120 = 84 + 45/120 = 129/120 - 129/120 simplified gives 43/40
- So, 21/30 + 15/40 = 43/40
In mixed form: 13/40
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