Add 28/35 and 7/21
28/35 + 7/21 is 17/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 35 × 3 = 105,
28/35 = 28 × 3/35 × 3 = 84/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
7/21 = 7 × 5/21 × 5 = 35/105 - Add the two like fractions:
84/105 + 35/105 = 84 + 35/105 = 119/105 - 119/105 simplified gives 17/15
- So, 28/35 + 7/21 = 17/15
In mixed form: 12/15
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