Add 30/40 and 15/70
30/40 + 15/70 is 27/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 70 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 40 × 7 = 280,
30/40 = 30 × 7/40 × 7 = 210/280 - Likewise, for the 2nd fraction, since 70 × 4 = 280,
15/70 = 15 × 4/70 × 4 = 60/280 - Add the two like fractions:
210/280 + 60/280 = 210 + 60/280 = 270/280 - 270/280 simplified gives 27/28
- So, 30/40 + 15/70 = 27/28
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 60/40+15/70 30/40+30/70 30/80+15/70 90/40+15/70 30/40+45/70 30/40+75/70