Add 42/90 and 21/80
42/90 + 21/80 is 35/48.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 90 × 8 = 720,
42/90 = 42 × 8/90 × 8 = 336/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
21/80 = 21 × 9/80 × 9 = 189/720 - Add the two like fractions:
336/720 + 189/720 = 336 + 189/720 = 525/720 - 525/720 simplified gives 35/48
- So, 42/90 + 21/80 = 35/48
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/90+21/80 42/90+42/80 42/90+63/80