Add 15/10 and 4/21, Solve 1 5/10 + 4/21 as a fraction

Add 15/10 and 4/21

1^st number: 1 5/10, 2^nd number: 4/21

15/10 + 4/21 is 71/42.

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

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 10 × 21 = 210,
15/10 = 15 × 21/10 × 21 = 315/210
Likewise, for the 2nd fraction, since 21 × 10 = 210,
4/21 = 4 × 10/21 × 10 = 40/210
Add the two like fractions:
315/210 + 40/210 = 315 + 40/210 = 355/210
355/210 simplified gives 71/42
So, 15/10 + 4/21 = 71/42
In mixed form: 129/42

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