Add 20/90 and 21/8
1st number: 20/90, 2nd number: 2 5/8
20/90 + 21/8 is 205/72.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 8 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 90 × 4 = 360,
20/90 = 20 × 4/90 × 4 = 80/360 - Likewise, for the 2nd fraction, since 8 × 45 = 360,
21/8 = 21 × 45/8 × 45 = 945/360 - Add the two like fractions:
80/360 + 945/360 = 80 + 945/360 = 1025/360 - 1025/360 simplified gives 205/72
- So, 20/90 + 21/8 = 205/72
In mixed form: 261/72
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/90+21/8 20/90+42/8 20/90+21/16 60/90+21/8 20/90+63/8 20/90+21/24 20/90+21/40 20/90+21/56