Add 30/80 and 81/7, Solve 30/80 + 11 4/7 as a fraction

Add 30/80 and 81/7

1^st number: 30/80, 2^nd number: 11 4/7

30/80 + 81/7 is 669/56.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 7 is 560

Next, find the equivalent fraction of both fractional numbers with denominator 560
For the 1st fraction, since 80 × 7 = 560,
30/80 = 30 × 7/80 × 7 = 210/560
Likewise, for the 2nd fraction, since 7 × 80 = 560,
81/7 = 81 × 80/7 × 80 = 6480/560
Add the two like fractions:
210/560 + 6480/560 = 210 + 6480/560 = 6690/560
6690/560 simplified gives 669/56
So, 30/80 + 81/7 = 669/56
In mixed form: 1153/56

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