Add 81/80 and 21/45
1st number: 1 1/80, 2nd number: 21/45
81/80 + 21/45 is 71/48.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 45 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
81/80 = 81 × 9/80 × 9 = 729/720 - Likewise, for the 2nd fraction, since 45 × 16 = 720,
21/45 = 21 × 16/45 × 16 = 336/720 - Add the two like fractions:
729/720 + 336/720 = 729 + 336/720 = 1065/720 - 1065/720 simplified gives 71/48
- So, 81/80 + 21/45 = 71/48
In mixed form: 123/48
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