Add 72/21 and 18/90, Solve 3 9/21 + 18/90 as a fraction

Add 72/21 and 18/90

1^st number: 3 9/21, 2^nd number: 18/90

72/21 + 18/90 is 127/35.

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,
18/90 = 18 × 7/90 × 7 = 126/630
Add the two like fractions:
2160/630 + 126/630 = 2160 + 126/630 = 2286/630
2286/630 simplified gives 127/35
So, 72/21 + 18/90 = 127/35
In mixed form: 322/35

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