Add 18/20 and 81/7, Solve 18/20 + 11 4/7 as a fraction

Add 18/20 and 81/7

1^st number: 18/20, 2^nd number: 11 4/7

18/20 + 81/7 is 873/70.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 7 is 140

Next, find the equivalent fraction of both fractional numbers with denominator 140
For the 1st fraction, since 20 × 7 = 140,
18/20 = 18 × 7/20 × 7 = 126/140
Likewise, for the 2nd fraction, since 7 × 20 = 140,
81/7 = 81 × 20/7 × 20 = 1620/140
Add the two like fractions:
126/140 + 1620/140 = 126 + 1620/140 = 1746/140
1746/140 simplified gives 873/70
So, 18/20 + 81/7 = 873/70
In mixed form: 1233/70

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