Add 21/40 and 20/30
21/40 + 20/30 is 143/120.
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,
20/30 = 20 × 4/30 × 4 = 80/120 - Add the two like fractions:
63/120 + 80/120 = 63 + 80/120 = 143/120 - So, 21/40 + 20/30 = 143/120
In mixed form: 123/120
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