Add 80/21 and 45/28
1st number: 3 17/21, 2nd number: 1 17/28
80/21 + 45/28 is 65/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
80/21 = 80 × 4/21 × 4 = 320/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
45/28 = 45 × 3/28 × 3 = 135/84 - Add the two like fractions:
320/84 + 135/84 = 320 + 135/84 = 455/84 - 455/84 simplified gives 65/12
- So, 80/21 + 45/28 = 65/12
In mixed form: 55/12
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