Add 28/21 and 90/4, Solve 1 7/21 + 22 2/4 as a fraction

Add 28/21 and 90/4

1^st number: 1 7/21, 2^nd number: 22 2/4

28/21 + 90/4 is 143/6.

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

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
28/21 = 28 × 4/21 × 4 = 112/84
Likewise, for the 2nd fraction, since 4 × 21 = 84,
90/4 = 90 × 21/4 × 21 = 1890/84
Add the two like fractions:
112/84 + 1890/84 = 112 + 1890/84 = 2002/84
2002/84 simplified gives 143/6
So, 28/21 + 90/4 = 143/6
In mixed form: 235/6

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