Add 80/21 and 9/10, Solve 3 17/21 + 9/10 as a fraction

Add 80/21 and 9/10

1^st number: 3 17/21, 2^nd number: 9/10

80/21 + 9/10 is 989/210.

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,
80/21 = 80 × 10/21 × 10 = 800/210
Likewise, for the 2nd fraction, since 10 × 21 = 210,
9/10 = 9 × 21/10 × 21 = 189/210
Add the two like fractions:
800/210 + 189/210 = 800 + 189/210 = 989/210
So, 80/21 + 9/10 = 989/210
In mixed form: 4149/210

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