Add 21/30 and 28/40
21/30 + 28/40 is 7/5.
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,
28/40 = 28 × 3/40 × 3 = 84/120 - Add the two like fractions:
84/120 + 84/120 = 84 + 84/120 = 168/120 - 168/120 simplified gives 7/5
- So, 21/30 + 28/40 = 7/5
In mixed form: 12/5
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