Add 30/42 and 40/15
1st number: 30/42, 2nd number: 2 10/15
30/42 + 40/15 is 71/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 15 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
30/42 = 30 × 5/42 × 5 = 150/210 - Likewise, for the 2nd fraction, since 15 × 14 = 210,
40/15 = 40 × 14/15 × 14 = 560/210 - Add the two like fractions:
150/210 + 560/210 = 150 + 560/210 = 710/210 - 710/210 simplified gives 71/21
- So, 30/42 + 40/15 = 71/21
In mixed form: 38/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 60/42+40/15 30/42+80/15 30/84+40/15 30/42+40/30 90/42+40/15 30/42+40/45 30/42+40/75