Add 15/21 and 80/7
1st number: 15/21, 2nd number: 11 3/7
15/21 + 80/7 is 85/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 7 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 21 × 1 = 21,
15/21 = 15 × 1/21 × 1 = 15/21 - Likewise, for the 2nd fraction, since 7 × 3 = 21,
80/7 = 80 × 3/7 × 3 = 240/21 - Add the two like fractions:
15/21 + 240/21 = 15 + 240/21 = 255/21 - 255/21 simplified gives 85/7
- So, 15/21 + 80/7 = 85/7
In mixed form: 121/7
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