Answers

Subtract 49/90 from 42/84

42/84 - 49/90 is -2/45.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 90 is 1260
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1260
2. For the 1st fraction, since 84 × 15 = 1260,
   42/84 = 42 × 15/84 × 15 = 630/1260
3. Likewise, for the 2nd fraction, since 90 × 14 = 1260,
   49/90 = 49 × 14/90 × 14 = 686/1260
4. Subtract the two like fractions:
   630/1260 - 686/1260 = 630 - 686/1260 = -56/1260
5. After reducing the fraction, the answer is -2/45

MathStep (Works offline)

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

Related: ⁴²/₈₄-⁹⁸/₉₀

Subtract Fractions Calculator