Add 81/4 and 18/21, Solve 20 1/4 + 18/21 as a fraction

Add 81/4 and 18/21

1^st number: 20 1/4, 2^nd number: 18/21

81/4 + 18/21 is 591/28.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 21 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 4 × 21 = 84,
81/4 = 81 × 21/4 × 21 = 1701/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
18/21 = 18 × 4/21 × 4 = 72/84
Add the two like fractions:
1701/84 + 72/84 = 1701 + 72/84 = 1773/84
1773/84 simplified gives 591/28
So, 81/4 + 18/21 = 591/28
In mixed form: 213/28

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