Add 9/10 and 30/21, Solve 9/10 + 1 9/21 as a fraction

Add 9/10 and 30/21

1^st number: 9/10, 2^nd number: 1 9/21

9/10 + 30/21 is 163/70.

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,
9/10 = 9 × 21/10 × 21 = 189/210
Likewise, for the 2nd fraction, since 21 × 10 = 210,
30/21 = 30 × 10/21 × 10 = 300/210
Add the two like fractions:
189/210 + 300/210 = 189 + 300/210 = 489/210
489/210 simplified gives 163/70
So, 9/10 + 30/21 = 163/70
In mixed form: 223/70

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