Add 21/80 and 20/18
1st number: 21/80, 2nd number: 1 2/18
21/80 + 20/18 is 989/720.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 18 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
21/80 = 21 × 9/80 × 9 = 189/720 - Likewise, for the 2nd fraction, since 18 × 40 = 720,
20/18 = 20 × 40/18 × 40 = 800/720 - Add the two like fractions:
189/720 + 800/720 = 189 + 800/720 = 989/720 - So, 21/80 + 20/18 = 989/720
In mixed form: 1269/720
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