Add 3/12 and 21/40
3/12 + 21/40 is 31/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 12 × 10 = 120,
3/12 = 3 × 10/12 × 10 = 30/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
21/40 = 21 × 3/40 × 3 = 63/120 - Add the two like fractions:
30/120 + 63/120 = 30 + 63/120 = 93/120 - 93/120 simplified gives 31/40
- So, 3/12 + 21/40 = 31/40
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