Add 10/18 and 80/21, Solve 10/18 + 3 17/21 as a fraction

Add 10/18 and 80/21

1^st number: 10/18, 2^nd number: 3 17/21

10/18 + 80/21 is 275/63.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
10/18 = 10 × 7/18 × 7 = 70/126
Likewise, for the 2nd fraction, since 21 × 6 = 126,
80/21 = 80 × 6/21 × 6 = 480/126
Add the two like fractions:
70/126 + 480/126 = 70 + 480/126 = 550/126
550/126 simplified gives 275/63
So, 10/18 + 80/21 = 275/63
In mixed form: 423/63

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