Add 40/42 and 42/90
40/42 + 42/90 is 149/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 42 × 15 = 630,
40/42 = 40 × 15/42 × 15 = 600/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
42/90 = 42 × 7/90 × 7 = 294/630 - Add the two like fractions:
600/630 + 294/630 = 600 + 294/630 = 894/630 - 894/630 simplified gives 149/105
- So, 40/42 + 42/90 = 149/105
In mixed form: 144/105
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 80/42+42/90 40/42+84/90 40/84+42/90