Add 90/21 and 28/56, Solve 4 6/21 + 28/56 as a fraction

Add 90/21 and 28/56

1^st number: 4 6/21, 2^nd number: 28/56

90/21 + 28/56 is 67/14.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 56 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 21 × 8 = 168,
90/21 = 90 × 8/21 × 8 = 720/168
Likewise, for the 2nd fraction, since 56 × 3 = 168,
28/56 = 28 × 3/56 × 3 = 84/168
Add the two like fractions:
720/168 + 84/168 = 720 + 84/168 = 804/168
804/168 simplified gives 67/14
So, 90/21 + 28/56 = 67/14
In mixed form: 411/14

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