Add 21/30 and 21/40
21/30 + 21/40 is 49/40.
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,
21/40 = 21 × 3/40 × 3 = 63/120 - Add the two like fractions:
84/120 + 63/120 = 84 + 63/120 = 147/120 - 147/120 simplified gives 49/40
- So, 21/30 + 21/40 = 49/40
In mixed form: 19/40
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