Add 21/35 and 28/21, Solve 21/35 + 1 7/21 as a fraction

Add 21/35 and 28/21

1^st number: 21/35, 2^nd number: 1 7/21

21/35 + 28/21 is 29/15.

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,
21/35 = 21 × 3/35 × 3 = 63/105
Likewise, for the 2nd fraction, since 21 × 5 = 105,
28/21 = 28 × 5/21 × 5 = 140/105
Add the two like fractions:
63/105 + 140/105 = 63 + 140/105 = 203/105
203/105 simplified gives 29/15
So, 21/35 + 28/21 = 29/15
In mixed form: 114/15

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