Add 7/21 and 90/28, Solve 7/21 + 3 6/28 as a fraction

Add 7/21 and 90/28

1^st number: 7/21, 2^nd number: 3 6/28

7/21 + 90/28 is 149/42.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
7/21 = 7 × 4/21 × 4 = 28/84
Likewise, for the 2nd fraction, since 28 × 3 = 84,
90/28 = 90 × 3/28 × 3 = 270/84
Add the two like fractions:
28/84 + 270/84 = 28 + 270/84 = 298/84
298/84 simplified gives 149/42
So, 7/21 + 90/28 = 149/42
In mixed form: 323/42

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