Add 4/8 and 2/21
4/8 + 2/21 is 25/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
4/8 = 4 × 21/8 × 21 = 84/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
2/21 = 2 × 8/21 × 8 = 16/168 - Add the two like fractions:
84/168 + 16/168 = 84 + 16/168 = 100/168 - 100/168 simplified gives 25/42
- So, 4/8 + 2/21 = 25/42
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 4/8+4/21 4/16+2/21 4/8+2/42 12/8+2/21 4/8+6/21 4/24+2/21 4/8+2/63 20/8+2/21 4/8+10/21 4/40+2/21 28/8+2/21 4/8+14/21 4/56+2/21