Add 15/42 and 21/10, Solve 15/42 + 2 1/10 as a fraction

Add 15/42 and 21/10

1^st number: 15/42, 2^nd number: 2 1/10

15/42 + 21/10 is 86/35.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 10 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 42 × 5 = 210,
15/42 = 15 × 5/42 × 5 = 75/210
Likewise, for the 2nd fraction, since 10 × 21 = 210,
21/10 = 21 × 21/10 × 21 = 441/210
Add the two like fractions:
75/210 + 441/210 = 75 + 441/210 = 516/210
516/210 simplified gives 86/35
So, 15/42 + 21/10 = 86/35
In mixed form: 216/35

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