Add 1/90 and 75/21, Solve 1/90 + 3 12/21 as a fraction

Add 1/90 and 75/21

1^st number: 1/90, 2^nd number: 3 12/21

1/90 + 75/21 is 2257/630.

Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 90 × 7 = 630,
1/90 = 1 × 7/90 × 7 = 7/630
Likewise, for the 2nd fraction, since 21 × 30 = 630,
75/21 = 75 × 30/21 × 30 = 2250/630
Add the two like fractions:
7/630 + 2250/630 = 7 + 2250/630 = 2257/630
So, 1/90 + 75/21 = 2257/630
In mixed form: 3367/630

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