Add 45/80 and 20/28
45/80 + 20/28 is 143/112.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 28 is 560
Next, find the equivalent fraction of both fractional numbers with denominator 560 - For the 1st fraction, since 80 × 7 = 560,
45/80 = 45 × 7/80 × 7 = 315/560 - Likewise, for the 2nd fraction, since 28 × 20 = 560,
20/28 = 20 × 20/28 × 20 = 400/560 - Add the two like fractions:
315/560 + 400/560 = 315 + 400/560 = 715/560 - 715/560 simplified gives 143/112
- So, 45/80 + 20/28 = 143/112
In mixed form: 131/112
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/80+20/28 45/80+40/28 45/80+20/56 45/80+60/28 45/80+20/84