Add 3/21 and 20/5, Solve 3/21 + 4 0/5 as a fraction

Add 3/21 and 20/5

1^st number: 3/21, 2^nd number: 4 0/5

3/21 + 20/5 is 29/7.

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,
3/21 = 3 × 5/21 × 5 = 15/105
Likewise, for the 2nd fraction, since 5 × 21 = 105,
20/5 = 20 × 21/5 × 21 = 420/105
Add the two like fractions:
15/105 + 420/105 = 15 + 420/105 = 435/105
435/105 simplified gives 29/7
So, 3/21 + 20/5 = 29/7
In mixed form: 41/7

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