Add 45/12 and 81/80
1st number: 3 9/12, 2nd number: 1 1/80
45/12 + 81/80 is 381/80.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 80 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 12 × 20 = 240,
45/12 = 45 × 20/12 × 20 = 900/240 - Likewise, for the 2nd fraction, since 80 × 3 = 240,
81/80 = 81 × 3/80 × 3 = 243/240 - Add the two like fractions:
900/240 + 243/240 = 900 + 243/240 = 1143/240 - 1143/240 simplified gives 381/80
- So, 45/12 + 81/80 = 381/80
In mixed form: 461/80
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