Add 18/40 and 21/80
18/40 + 21/80 is 57/80.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 80 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 40 × 2 = 80,
18/40 = 18 × 2/40 × 2 = 36/80 - Likewise, for the 2nd fraction, since 80 × 1 = 80,
21/80 = 21 × 1/80 × 1 = 21/80 - Add the two like fractions:
36/80 + 21/80 = 36 + 21/80 = 57/80 - So, 18/40 + 21/80 = 57/80
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