Add 21/80 and 15/20
21/80 + 15/20 is 81/80.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 20 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 80 × 1 = 80,
21/80 = 21 × 1/80 × 1 = 21/80 - Likewise, for the 2nd fraction, since 20 × 4 = 80,
15/20 = 15 × 4/20 × 4 = 60/80 - Add the two like fractions:
21/80 + 60/80 = 21 + 60/80 = 81/80 - So, 21/80 + 15/20 = 81/80
In mixed form: 11/80
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