Add 42/84 and 15/8
1st number: 42/84, 2nd number: 1 7/8
42/84 + 15/8 is 19/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 8 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 84 × 2 = 168,
42/84 = 42 × 2/84 × 2 = 84/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
15/8 = 15 × 21/8 × 21 = 315/168 - Add the two like fractions:
84/168 + 315/168 = 84 + 315/168 = 399/168 - 399/168 simplified gives 19/8
- So, 42/84 + 15/8 = 19/8
In mixed form: 23/8
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/84+30/8 42/84+15/16 42/84+45/8 42/84+15/24 42/84+75/8 42/84+15/40 42/84+15/56