Add 70/4 and 42/21
1st number: 17 2/4, 2nd number: 2 0/21
70/4 + 42/21 is 39/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 4 × 21 = 84,
70/4 = 70 × 21/4 × 21 = 1470/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
42/21 = 42 × 4/21 × 4 = 168/84 - Add the two like fractions:
1470/84 + 168/84 = 1470 + 168/84 = 1638/84 - 1638/84 simplified gives 39/2
- So, 70/4 + 42/21 = 39/2
In mixed form: 191/2
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 70/4+84/21 70/8+42/21 70/12+42/21 70/4+42/63 70/20+42/21 70/28+42/21