Add 30/70 and 54/80
30/70 + 54/80 is 309/280.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 80 is 560
Next, find the equivalent fraction of both fractional numbers with denominator 560 - For the 1st fraction, since 70 × 8 = 560,
30/70 = 30 × 8/70 × 8 = 240/560 - Likewise, for the 2nd fraction, since 80 × 7 = 560,
54/80 = 54 × 7/80 × 7 = 378/560 - Add the two like fractions:
240/560 + 378/560 = 240 + 378/560 = 618/560 - 618/560 simplified gives 309/280
- So, 30/70 + 54/80 = 309/280
In mixed form: 129/280
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 60/70+54/80 90/70+54/80