Add 15/5 and 1/21, Solve 3 0/5 + 1/21 as a fraction

Add 15/5 and 1/21

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

15/5 + 1/21 is 64/21.

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

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 5 × 21 = 105,
15/5 = 15 × 21/5 × 21 = 315/105
Likewise, for the 2nd fraction, since 21 × 5 = 105,
1/21 = 1 × 5/21 × 5 = 5/105
Add the two like fractions:
315/105 + 5/105 = 315 + 5/105 = 320/105
320/105 simplified gives 64/21
So, 15/5 + 1/21 = 64/21
In mixed form: 31/21

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