Add 21/90 and 1/72
21/90 + 1/72 is 89/360.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 90 × 4 = 360,
21/90 = 21 × 4/90 × 4 = 84/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
1/72 = 1 × 5/72 × 5 = 5/360 - Add the two like fractions:
84/360 + 5/360 = 84 + 5/360 = 89/360 - So, 21/90 + 1/72 = 89/360
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/90+1/72 21/90+2/72 63/90+1/72 21/90+3/72 21/90+5/72 21/90+7/72