Add 20/72 and 18/45
20/72 + 18/45 is 61/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 45 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
20/72 = 20 × 5/72 × 5 = 100/360 - Likewise, for the 2nd fraction, since 45 × 8 = 360,
18/45 = 18 × 8/45 × 8 = 144/360 - Add the two like fractions:
100/360 + 144/360 = 100 + 144/360 = 244/360 - 244/360 simplified gives 61/90
- So, 20/72 + 18/45 = 61/90
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/72+18/45 20/72+36/45 20/72+18/90 60/72+18/45 20/72+54/45 20/72+90/45