Add 42/90 and 18/40
42/90 + 18/40 is 11/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 90 × 4 = 360,
42/90 = 42 × 4/90 × 4 = 168/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
18/40 = 18 × 9/40 × 9 = 162/360 - Add the two like fractions:
168/360 + 162/360 = 168 + 162/360 = 330/360 - 330/360 simplified gives 11/12
- So, 42/90 + 18/40 = 11/12
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/90+18/40 42/90+36/40 42/90+18/80 42/90+54/40 42/90+90/40