Answers

Subtract 45/70 from 30/90

30/90 - 45/70 is -13/42.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 90 and 70 is 630
   
   Next, find the equivalent fraction of both fractional numbers with denominator 630
2. For the 1st fraction, since 90 × 7 = 630,
   30/90 = 30 × 7/90 × 7 = 210/630
3. Likewise, for the 2nd fraction, since 70 × 9 = 630,
   45/70 = 45 × 9/70 × 9 = 405/630
4. Subtract the two like fractions:
   210/630 - 405/630 = 210 - 405/630 = -195/630
5. After reducing the fraction, the answer is -13/42

MathStep (Works offline)

Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad

Related: ⁶⁰/₉₀-⁴⁵/₇₀ ³⁰/₉₀-⁹⁰/₇₀

Subtract Fractions Calculator