Add 12/90 and 42/80
12/90 + 42/80 is 79/120.
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,
12/90 = 12 × 8/90 × 8 = 96/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
42/80 = 42 × 9/80 × 9 = 378/720 - Add the two like fractions:
96/720 + 378/720 = 96 + 378/720 = 474/720 - 474/720 simplified gives 79/120
- So, 12/90 + 42/80 = 79/120
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/90+42/80 12/90+84/80 36/90+42/80 60/90+42/80 84/90+42/80