Add 21/5 and 90/72
1st number: 4 1/5, 2nd number: 1 18/72
21/5 + 90/72 is 109/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 5 × 72 = 360,
21/5 = 21 × 72/5 × 72 = 1512/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
90/72 = 90 × 5/72 × 5 = 450/360 - Add the two like fractions:
1512/360 + 450/360 = 1512 + 450/360 = 1962/360 - 1962/360 simplified gives 109/20
- So, 21/5 + 90/72 = 109/20
In mixed form: 59/20
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/5+90/72 21/10+90/72 63/5+90/72 21/15+90/72 21/25+90/72 21/35+90/72