Add 21/80 and 12/9
1st number: 21/80, 2nd number: 1 3/9
21/80 + 12/9 is 383/240.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 9 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 9 × 80 = 720,
12/9 = 12 × 80/9 × 80 = 960/720 - Add the two like fractions:
189/720 + 960/720 = 189 + 960/720 = 1149/720 - 1149/720 simplified gives 383/240
- So, 21/80 + 12/9 = 383/240
In mixed form: 1143/240
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