Add 9/20 and 21/40
9/20 + 21/40 is 39/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 40 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 20 × 2 = 40,
9/20 = 9 × 2/20 × 2 = 18/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
21/40 = 21 × 1/40 × 1 = 21/40 - Add the two like fractions:
18/40 + 21/40 = 18 + 21/40 = 39/40 - So, 9/20 + 21/40 = 39/40
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