Add 80/28 and 30/21
1st number: 2 24/28, 2nd number: 1 9/21
80/28 + 30/21 is 30/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
80/28 = 80 × 3/28 × 3 = 240/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
30/21 = 30 × 4/21 × 4 = 120/84 - Add the two like fractions:
240/84 + 120/84 = 240 + 120/84 = 360/84 - 360/84 simplified gives 30/7
- So, 80/28 + 30/21 = 30/7
In mixed form: 42/7
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