Add 42/21 and 6/90, Solve 2 0/21 + 6/90 as a fraction

Add 42/21 and 6/90

1^st number: 2 0/21, 2^nd number: 6/90

42/21 + 6/90 is 31/15.

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

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 21 × 30 = 630,
42/21 = 42 × 30/21 × 30 = 1260/630
Likewise, for the 2nd fraction, since 90 × 7 = 630,
6/90 = 6 × 7/90 × 7 = 42/630
Add the two like fractions:
1260/630 + 42/630 = 1260 + 42/630 = 1302/630
1302/630 simplified gives 31/15
So, 42/21 + 6/90 = 31/15
In mixed form: 21/15

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