Add 80/21 and 35/5, Solve 3 17/21 + 7 0/5 as a fraction

Add 80/21 and 35/5

1^st number: 3 17/21, 2^nd number: 7 0/5

80/21 + 35/5 is 227/21.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 5 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 21 × 5 = 105,
80/21 = 80 × 5/21 × 5 = 400/105
Likewise, for the 2nd fraction, since 5 × 21 = 105,
35/5 = 35 × 21/5 × 21 = 735/105
Add the two like fractions:
400/105 + 735/105 = 400 + 735/105 = 1135/105
1135/105 simplified gives 227/21
So, 80/21 + 35/5 = 227/21
In mixed form: 1017/21

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