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

Add 90/27 and 3/21

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

90/27 + 3/21 is 73/21.

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

Next, find the equivalent fraction of both fractional numbers with denominator 189
For the 1st fraction, since 27 × 7 = 189,
90/27 = 90 × 7/27 × 7 = 630/189
Likewise, for the 2nd fraction, since 21 × 9 = 189,
3/21 = 3 × 9/21 × 9 = 27/189
Add the two like fractions:
630/189 + 27/189 = 630 + 27/189 = 657/189
657/189 simplified gives 73/21
So, 90/27 + 3/21 = 73/21
In mixed form: 310/21

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