Add 15/21 and 4/10, Solve 15/21 + 4/10 as a fraction

Add 15/21 and 4/10

15/21 + 4/10 is 39/35.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 10 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 21 × 10 = 210,
15/21 = 15 × 10/21 × 10 = 150/210
Likewise, for the 2nd fraction, since 10 × 21 = 210,
4/10 = 4 × 21/10 × 21 = 84/210
Add the two like fractions:
150/210 + 84/210 = 150 + 84/210 = 234/210
234/210 simplified gives 39/35
So, 15/21 + 4/10 = 39/35
In mixed form: 14/35

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