Add 81/7 and 21/90, Solve 11 4/7 + 21/90 as a fraction

Add 81/7 and 21/90

1^st number: 11 4/7, 2^nd number: 21/90

81/7 + 21/90 is 2479/210.

Find the least common denominator or LCM of the two denominators:
LCM of 7 and 90 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 7 × 90 = 630,
81/7 = 81 × 90/7 × 90 = 7290/630
Likewise, for the 2nd fraction, since 90 × 7 = 630,
21/90 = 21 × 7/90 × 7 = 147/630
Add the two like fractions:
7290/630 + 147/630 = 7290 + 147/630 = 7437/630
7437/630 simplified gives 2479/210
So, 81/7 + 21/90 = 2479/210
In mixed form: 11169/210

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