Add 18/90 and 2/21
18/90 + 2/21 is 31/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
18/90 = 18 × 7/90 × 7 = 126/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
2/21 = 2 × 30/21 × 30 = 60/630 - Add the two like fractions:
126/630 + 60/630 = 126 + 60/630 = 186/630 - 186/630 simplified gives 31/105
- So, 18/90 + 2/21 = 31/105
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/90+2/21 18/90+4/21 18/90+2/42 54/90+2/21 18/90+6/21 18/90+2/63 18/90+10/21 18/90+14/21