Add 21/56 and 90/84, Solve 21/56 + 1 6/84 as a fraction

Add 21/56 and 90/84

1^st number: 21/56, 2^nd number: 1 6/84

21/56 + 90/84 is 81/56.

Find the least common denominator or LCM of the two denominators:
LCM of 56 and 84 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 56 × 3 = 168,
21/56 = 21 × 3/56 × 3 = 63/168
Likewise, for the 2nd fraction, since 84 × 2 = 168,
90/84 = 90 × 2/84 × 2 = 180/168
Add the two like fractions:
63/168 + 180/168 = 63 + 180/168 = 243/168
243/168 simplified gives 81/56
So, 21/56 + 90/84 = 81/56
In mixed form: 125/56

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