Add 4/21 and 90/14, Solve 4/21 + 6 6/14 as a fraction

Add 4/21 and 90/14

1^st number: 4/21, 2^nd number: 6 6/14

4/21 + 90/14 is 139/21.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 14 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 21 × 2 = 42,
4/21 = 4 × 2/21 × 2 = 8/42
Likewise, for the 2nd fraction, since 14 × 3 = 42,
90/14 = 90 × 3/14 × 3 = 270/42
Add the two like fractions:
8/42 + 270/42 = 8 + 270/42 = 278/42
278/42 simplified gives 139/21
So, 4/21 + 90/14 = 139/21
In mixed form: 613/21

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