Add 20/45 and 28/42
20/45 + 28/42 is 10/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 42 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 45 × 14 = 630,
20/45 = 20 × 14/45 × 14 = 280/630 - Likewise, for the 2nd fraction, since 42 × 15 = 630,
28/42 = 28 × 15/42 × 15 = 420/630 - Add the two like fractions:
280/630 + 420/630 = 280 + 420/630 = 700/630 - 700/630 simplified gives 10/9
- So, 20/45 + 28/42 = 10/9
In mixed form: 11/9
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/45+28/42 20/45+56/42 20/90+28/42 20/45+28/84 60/45+28/42 20/45+84/42