Add 21/28 and 90/84, Solve 21/28 + 1 6/84 as a fraction

Add 21/28 and 90/84

1^st number: 21/28, 2^nd number: 1 6/84

21/28 + 90/84 is 51/28.

Find the least common denominator or LCM of the two denominators:
LCM of 28 and 84 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 28 × 3 = 84,
21/28 = 21 × 3/28 × 3 = 63/84
Likewise, for the 2nd fraction, since 84 × 1 = 84,
90/84 = 90 × 1/84 × 1 = 90/84
Add the two like fractions:
63/84 + 90/84 = 63 + 90/84 = 153/84
153/84 simplified gives 51/28
So, 21/28 + 90/84 = 51/28
In mixed form: 123/28

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