Add 70/21 and 42/90, Solve 3 7/21 + 42/90 as a fraction

Add 70/21 and 42/90

1^st number: 3 7/21, 2^nd number: 42/90

70/21 + 42/90 is 19/5.

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,
70/21 = 70 × 30/21 × 30 = 2100/630
Likewise, for the 2nd fraction, since 90 × 7 = 630,
42/90 = 42 × 7/90 × 7 = 294/630
Add the two like fractions:
2100/630 + 294/630 = 2100 + 294/630 = 2394/630
2394/630 simplified gives 19/5
So, 70/21 + 42/90 = 19/5
In mixed form: 34/5

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