Add 15/45 and 42/90
15/45 + 42/90 is 4/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 45 × 2 = 90,
15/45 = 15 × 2/45 × 2 = 30/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
42/90 = 42 × 1/90 × 1 = 42/90 - Add the two like fractions:
30/90 + 42/90 = 30 + 42/90 = 72/90 - 72/90 simplified gives 4/5
- So, 15/45 + 42/90 = 4/5
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 30/45+42/90 15/45+84/90 15/90+42/90 75/45+42/90