Add 15/20 and 45/80
15/20 + 45/80 is 21/16.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 80 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 20 × 4 = 80,
15/20 = 15 × 4/20 × 4 = 60/80 - Likewise, for the 2nd fraction, since 80 × 1 = 80,
45/80 = 45 × 1/80 × 1 = 45/80 - Add the two like fractions:
60/80 + 45/80 = 60 + 45/80 = 105/80 - 105/80 simplified gives 21/16
- So, 15/20 + 45/80 = 21/16
In mixed form: 15/16
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