Add 3/15 and 63/42, Solve 3/15 + 1 21/42 as a fraction

Add 3/15 and 63/42

1^st number: 3/15, 2^nd number: 1 21/42

3/15 + 63/42 is 17/10.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 15 × 14 = 210,
3/15 = 3 × 14/15 × 14 = 42/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
63/42 = 63 × 5/42 × 5 = 315/210
Add the two like fractions:
42/210 + 315/210 = 42 + 315/210 = 357/210
357/210 simplified gives 17/10
So, 3/15 + 63/42 = 17/10
In mixed form: 17/10

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