Add 21/6 and 15/45, Solve 3 3/6 + 15/45 as a fraction

Add 21/6 and 15/45

1^st number: 3 3/6, 2^nd number: 15/45

21/6 + 15/45 is 23/6.

Find the least common denominator or LCM of the two denominators:
LCM of 6 and 45 is 90

Next, find the equivalent fraction of both fractional numbers with denominator 90
For the 1st fraction, since 6 × 15 = 90,
21/6 = 21 × 15/6 × 15 = 315/90
Likewise, for the 2nd fraction, since 45 × 2 = 90,
15/45 = 15 × 2/45 × 2 = 30/90
Add the two like fractions:
315/90 + 30/90 = 315 + 30/90 = 345/90
345/90 simplified gives 23/6
So, 21/6 + 15/45 = 23/6
In mixed form: 35/6

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