Add 21/4 and 70/90
1st number: 5 1/4, 2nd number: 70/90
21/4 + 70/90 is 217/36.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 4 × 45 = 180,
21/4 = 21 × 45/4 × 45 = 945/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
70/90 = 70 × 2/90 × 2 = 140/180 - Add the two like fractions:
945/180 + 140/180 = 945 + 140/180 = 1085/180 - 1085/180 simplified gives 217/36
- So, 21/4 + 70/90 = 217/36
In mixed form: 61/36
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/4+70/90 21/8+70/90 63/4+70/90 21/12+70/90 21/20+70/90 21/28+70/90