Add 70/21 and 24/90, Solve 3 7/21 + 24/90 as a fraction

Add 70/21 and 24/90

1^st number: 3 7/21, 2^nd number: 24/90

70/21 + 24/90 is 18/5.

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,
24/90 = 24 × 7/90 × 7 = 168/630
Add the two like fractions:
2100/630 + 168/630 = 2100 + 168/630 = 2268/630
2268/630 simplified gives 18/5
So, 70/21 + 24/90 = 18/5
In mixed form: 33/5

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