Add 40/3 and 80/21
1st number: 13 1/3, 2nd number: 3 17/21
40/3 + 80/21 is 120/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 3 and 21 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 3 × 7 = 21,
40/3 = 40 × 7/3 × 7 = 280/21 - Likewise, for the 2nd fraction, since 21 × 1 = 21,
80/21 = 80 × 1/21 × 1 = 80/21 - Add the two like fractions:
280/21 + 80/21 = 280 + 80/21 = 360/21 - 360/21 simplified gives 120/7
- So, 40/3 + 80/21 = 120/7
In mixed form: 171/7
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