Add 80/21 and 5/25, Solve 3 17/21 + 5/25 as a fraction

Add 80/21 and 5/25

1^st number: 3 17/21, 2^nd number: 5/25

80/21 + 5/25 is 421/105.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 25 is 525

Next, find the equivalent fraction of both fractional numbers with denominator 525
For the 1st fraction, since 21 × 25 = 525,
80/21 = 80 × 25/21 × 25 = 2000/525
Likewise, for the 2nd fraction, since 25 × 21 = 525,
5/25 = 5 × 21/25 × 21 = 105/525
Add the two like fractions:
2000/525 + 105/525 = 2000 + 105/525 = 2105/525
2105/525 simplified gives 421/105
So, 80/21 + 5/25 = 421/105
In mixed form: 41/105

MathStep (Works offline)

Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad