Add 42/90 and 28/70
42/90 + 28/70 is 13/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 70 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
42/90 = 42 × 7/90 × 7 = 294/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
28/70 = 28 × 9/70 × 9 = 252/630 - Add the two like fractions:
294/630 + 252/630 = 294 + 252/630 = 546/630 - 546/630 simplified gives 13/15
- So, 42/90 + 28/70 = 13/15
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/90+28/70 42/90+56/70 42/90+84/70