Add 4/21 and 90/27, Solve 4/21 + 3 9/27 as a fraction

Add 4/21 and 90/27

1^st number: 4/21, 2^nd number: 3 9/27

4/21 + 90/27 is 74/21.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 27 is 189

Next, find the equivalent fraction of both fractional numbers with denominator 189
For the 1st fraction, since 21 × 9 = 189,
4/21 = 4 × 9/21 × 9 = 36/189
Likewise, for the 2nd fraction, since 27 × 7 = 189,
90/27 = 90 × 7/27 × 7 = 630/189
Add the two like fractions:
36/189 + 630/189 = 36 + 630/189 = 666/189
666/189 simplified gives 74/21
So, 4/21 + 90/27 = 74/21
In mixed form: 311/21

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