Add 30/18 and 81/80
1st number: 1 12/18, 2nd number: 1 1/80
30/18 + 81/80 is 643/240.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 18 × 40 = 720,
30/18 = 30 × 40/18 × 40 = 1200/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
81/80 = 81 × 9/80 × 9 = 729/720 - Add the two like fractions:
1200/720 + 729/720 = 1200 + 729/720 = 1929/720 - 1929/720 simplified gives 643/240
- So, 30/18 + 81/80 = 643/240
In mixed form: 2163/240
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