Add 42/90 and 54/70
42/90 + 54/70 is 26/21.
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,
54/70 = 54 × 9/70 × 9 = 486/630 - Add the two like fractions:
294/630 + 486/630 = 294 + 486/630 = 780/630 - 780/630 simplified gives 26/21
- So, 42/90 + 54/70 = 26/21
In mixed form: 15/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/90+54/70