Add 20/45 and 81/80
1st number: 20/45, 2nd number: 1 1/80
20/45 + 81/80 is 1049/720.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 45 × 16 = 720,
20/45 = 20 × 16/45 × 16 = 320/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
81/80 = 81 × 9/80 × 9 = 729/720 - Add the two like fractions:
320/720 + 729/720 = 320 + 729/720 = 1049/720 - So, 20/45 + 81/80 = 1049/720
In mixed form: 1329/720
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