Add 18/42 and 90/45
1st number: 18/42, 2nd number: 2 0/45
18/42 + 90/45 is 17/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 45 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 42 × 15 = 630,
18/42 = 18 × 15/42 × 15 = 270/630 - Likewise, for the 2nd fraction, since 45 × 14 = 630,
90/45 = 90 × 14/45 × 14 = 1260/630 - Add the two like fractions:
270/630 + 1260/630 = 270 + 1260/630 = 1530/630 - 1530/630 simplified gives 17/7
- So, 18/42 + 90/45 = 17/7
In mixed form: 23/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/42+90/45 18/84+90/45 54/42+90/45 90/42+90/45