Add 90/30 and 81/42, Solve 3 0/30 + 1 39/42 as a fraction

Add 90/30 and 81/42

1^st number: 3 0/30, 2^nd number: 1 39/42

90/30 + 81/42 is 69/14.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 30 × 7 = 210,
90/30 = 90 × 7/30 × 7 = 630/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
81/42 = 81 × 5/42 × 5 = 405/210
Add the two like fractions:
630/210 + 405/210 = 630 + 405/210 = 1035/210
1035/210 simplified gives 69/14
So, 90/30 + 81/42 = 69/14
In mixed form: 413/14

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