Add 3/5 and 63/42, Solve 3/5 + 1 21/42 as a fraction

Add 3/5 and 63/42

1^st number: 3/5, 2^nd number: 1 21/42

3/5 + 63/42 is 21/10.

Find the least common denominator or LCM of the two denominators:
LCM of 5 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 5 × 42 = 210,
3/5 = 3 × 42/5 × 42 = 126/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
63/42 = 63 × 5/42 × 5 = 315/210
Add the two like fractions:
126/210 + 315/210 = 126 + 315/210 = 441/210
441/210 simplified gives 21/10
So, 3/5 + 63/42 = 21/10
In mixed form: 21/10

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