Add 4/21 and 40/25, Solve 4/21 + 1 15/25 as a fraction

Add 4/21 and 40/25

1^st number: 4/21, 2^nd number: 1 15/25

4/21 + 40/25 is 188/105.

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,
4/21 = 4 × 25/21 × 25 = 100/525
Likewise, for the 2nd fraction, since 25 × 21 = 525,
40/25 = 40 × 21/25 × 21 = 840/525
Add the two like fractions:
100/525 + 840/525 = 100 + 840/525 = 940/525
940/525 simplified gives 188/105
So, 4/21 + 40/25 = 188/105
In mixed form: 183/105

MathStep (Works offline)

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