Add 10/18 and 15/21, Solve 10/18 + 15/21 as a fraction

Add 10/18 and 15/21

10/18 + 15/21 is 80/63.

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,
15/21 = 15 × 6/21 × 6 = 90/126
Add the two like fractions:
70/126 + 90/126 = 70 + 90/126 = 160/126
160/126 simplified gives 80/63
So, 10/18 + 15/21 = 80/63
In mixed form: 117/63

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