Add 21/40 and 12/20
21/40 + 12/20 is 9/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 20 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 40 × 1 = 40,
21/40 = 21 × 1/40 × 1 = 21/40 - Likewise, for the 2nd fraction, since 20 × 2 = 40,
12/20 = 12 × 2/20 × 2 = 24/40 - Add the two like fractions:
21/40 + 24/40 = 21 + 24/40 = 45/40 - 45/40 simplified gives 9/8
- So, 21/40 + 12/20 = 9/8
In mixed form: 11/8
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