Add 20/12 and 18/7, Solve 1 8/12 + 2 4/7 as a fraction

Add 20/12 and 18/7

1^st number: 1 8/12, 2^nd number: 2 4/7

20/12 + 18/7 is 89/21.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 7 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 12 × 7 = 84,
20/12 = 20 × 7/12 × 7 = 140/84
Likewise, for the 2nd fraction, since 7 × 12 = 84,
18/7 = 18 × 12/7 × 12 = 216/84
Add the two like fractions:
140/84 + 216/84 = 140 + 216/84 = 356/84
356/84 simplified gives 89/21
So, 20/12 + 18/7 = 89/21
In mixed form: 45/21

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