Add 42/21 and 4/90, Solve 2 0/21 + 4/90 as a fraction

Add 42/21 and 4/90

1^st number: 2 0/21, 2^nd number: 4/90

42/21 + 4/90 is 92/45.

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,
4/90 = 4 × 7/90 × 7 = 28/630
Add the two like fractions:
1260/630 + 28/630 = 1260 + 28/630 = 1288/630
1288/630 simplified gives 92/45
So, 42/21 + 4/90 = 92/45
In mixed form: 22/45

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