Add 28/21 and 24/90, Solve 1 7/21 + 24/90 as a fraction

Add 28/21 and 24/90

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

28/21 + 24/90 is 8/5.

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,
28/21 = 28 × 30/21 × 30 = 840/630
Likewise, for the 2nd fraction, since 90 × 7 = 630,
24/90 = 24 × 7/90 × 7 = 168/630
Add the two like fractions:
840/630 + 168/630 = 840 + 168/630 = 1008/630
1008/630 simplified gives 8/5
So, 28/21 + 24/90 = 8/5
In mixed form: 13/5

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