Add 20/21 and 4/80
20/21 + 4/80 is 421/420.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 21 × 80 = 1680,
20/21 = 20 × 80/21 × 80 = 1600/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
4/80 = 4 × 21/80 × 21 = 84/1680 - Add the two like fractions:
1600/1680 + 84/1680 = 1600 + 84/1680 = 1684/1680 - 1684/1680 simplified gives 421/420
- So, 20/21 + 4/80 = 421/420
In mixed form: 11/420
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/21+4/80 20/21+8/80 20/42+4/80 60/21+4/80 20/21+12/80 20/63+4/80 20/21+20/80 20/21+28/80