Add 15/10 and 21/30, Solve 1 5/10 + 21/30 as a fraction

Add 15/10 and 21/30

1^st number: 1 5/10, 2^nd number: 21/30

15/10 + 21/30 is 11/5.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 30 is 30

Next, find the equivalent fraction of both fractional numbers with denominator 30
For the 1st fraction, since 10 × 3 = 30,
15/10 = 15 × 3/10 × 3 = 45/30
Likewise, for the 2nd fraction, since 30 × 1 = 30,
21/30 = 21 × 1/30 × 1 = 21/30
Add the two like fractions:
45/30 + 21/30 = 45 + 21/30 = 66/30
66/30 simplified gives 11/5
So, 15/10 + 21/30 = 11/5
In mixed form: 21/5

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