Add 15/90 and 90/70
1st number: 15/90, 2nd number: 1 20/70
15/90 + 90/70 is 61/42.
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,
15/90 = 15 × 7/90 × 7 = 105/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
90/70 = 90 × 9/70 × 9 = 810/630 - Add the two like fractions:
105/630 + 810/630 = 105 + 810/630 = 915/630 - 915/630 simplified gives 61/42
- So, 15/90 + 90/70 = 61/42
In mixed form: 119/42
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 30/90+90/70 45/90+90/70 75/90+90/70