Add 24/40 and 42/21
1st number: 24/40, 2nd number: 2 0/21
24/40 + 42/21 is 13/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
24/40 = 24 × 21/40 × 21 = 504/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
42/21 = 42 × 40/21 × 40 = 1680/840 - Add the two like fractions:
504/840 + 1680/840 = 504 + 1680/840 = 2184/840 - 2184/840 simplified gives 13/5
- So, 24/40 + 42/21 = 13/5
In mixed form: 23/5
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 48/40+42/21 24/40+84/21 24/80+42/21 72/40+42/21 24/40+42/63