Add 42/9 and 21/40
1st number: 4 6/9, 2nd number: 21/40
42/9 + 21/40 is 623/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 9 × 40 = 360,
42/9 = 42 × 40/9 × 40 = 1680/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
21/40 = 21 × 9/40 × 9 = 189/360 - Add the two like fractions:
1680/360 + 189/360 = 1680 + 189/360 = 1869/360 - 1869/360 simplified gives 623/120
- So, 42/9 + 21/40 = 623/120
In mixed form: 523/120
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/9+21/40 42/9+42/40 42/18+21/40 42/9+21/80 42/9+63/40 42/27+21/40 42/45+21/40 42/63+21/40