Add 15/21 and 10/5
1st number: 15/21, 2nd number: 2 0/5
15/21 + 10/5 is 19/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 5 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
15/21 = 15 × 5/21 × 5 = 75/105 - Likewise, for the 2nd fraction, since 5 × 21 = 105,
10/5 = 10 × 21/5 × 21 = 210/105 - Add the two like fractions:
75/105 + 210/105 = 75 + 210/105 = 285/105 - 285/105 simplified gives 19/7
- So, 15/21 + 10/5 = 19/7
In mixed form: 25/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 30/21+10/5 15/21+20/5 15/42+10/5 45/21+10/5 15/21+30/5 15/63+10/5 15/21+10/15 75/21+10/5 15/21+50/5 15/21+10/25 15/21+70/5 15/21+10/35