Add 81/80 and 20/12
1st number: 1 1/80, 2nd number: 1 8/12
81/80 + 20/12 is 643/240.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 12 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 80 × 3 = 240,
81/80 = 81 × 3/80 × 3 = 243/240 - Likewise, for the 2nd fraction, since 12 × 20 = 240,
20/12 = 20 × 20/12 × 20 = 400/240 - Add the two like fractions:
243/240 + 400/240 = 243 + 400/240 = 643/240 - So, 81/80 + 20/12 = 643/240
In mixed form: 2163/240
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