Add 72/21 and 27/90, Solve 3 9/21 + 27/90 as a fraction

Add 72/21 and 27/90

1^st number: 3 9/21, 2^nd number: 27/90

72/21 + 27/90 is 261/70.

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,
72/21 = 72 × 30/21 × 30 = 2160/630
Likewise, for the 2nd fraction, since 90 × 7 = 630,
27/90 = 27 × 7/90 × 7 = 189/630
Add the two like fractions:
2160/630 + 189/630 = 2160 + 189/630 = 2349/630
2349/630 simplified gives 261/70
So, 72/21 + 27/90 = 261/70
In mixed form: 351/70

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