Add 80/90 and 80/21, Solve 80/90 + 3 17/21 as a fraction

Add 80/90 and 80/21

1^st number: 80/90, 2^nd number: 3 17/21

80/90 + 80/21 is 296/63.

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,
80/90 = 80 × 7/90 × 7 = 560/630
Likewise, for the 2nd fraction, since 21 × 30 = 630,
80/21 = 80 × 30/21 × 30 = 2400/630
Add the two like fractions:
560/630 + 2400/630 = 560 + 2400/630 = 2960/630
2960/630 simplified gives 296/63
So, 80/90 + 80/21 = 296/63
In mixed form: 444/63

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