Add 45/90 and 80/21, Solve 45/90 + 3 17/21 as a fraction

Add 45/90 and 80/21

1^st number: 45/90, 2^nd number: 3 17/21

45/90 + 80/21 is 181/42.

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,
45/90 = 45 × 7/90 × 7 = 315/630
Likewise, for the 2nd fraction, since 21 × 30 = 630,
80/21 = 80 × 30/21 × 30 = 2400/630
Add the two like fractions:
315/630 + 2400/630 = 315 + 2400/630 = 2715/630
2715/630 simplified gives 181/42
So, 45/90 + 80/21 = 181/42
In mixed form: 413/42

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