Add 28/21 and 80/15
1st number: 1 7/21, 2nd number: 5 5/15
28/21 + 80/15 is 20/3.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
28/21 = 28 × 5/21 × 5 = 140/105 - Likewise, for the 2nd fraction, since 15 × 7 = 105,
80/15 = 80 × 7/15 × 7 = 560/105 - Add the two like fractions:
140/105 + 560/105 = 140 + 560/105 = 700/105 - 700/105 simplified gives 20/3
- So, 28/21 + 80/15 = 20/3
In mixed form: 62/3
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