Subtract 42/90 from 45/70
45/70 - 42/90 is 37/210.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
45/70 = 45 × 9/70 × 9 = 405/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
42/90 = 42 × 7/90 × 7 = 294/630 - Subtract the two like fractions:
405/630 - 294/630 = 405 - 294/630 = 111/630 - After reducing the fraction, the answer is 37/210
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/70-42/90 45/70-84/90