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

Add 24/90 and 70/21

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

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

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,
24/90 = 24 × 7/90 × 7 = 168/630
Likewise, for the 2nd fraction, since 21 × 30 = 630,
70/21 = 70 × 30/21 × 30 = 2100/630
Add the two like fractions:
168/630 + 2100/630 = 168 + 2100/630 = 2268/630
2268/630 simplified gives 18/5
So, 24/90 + 70/21 = 18/5
In mixed form: 33/5

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