Subtract 42/45 from 28/42
28/42 - 42/45 is -4/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 45 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 42 × 15 = 630,
28/42 = 28 × 15/42 × 15 = 420/630 - Likewise, for the 2nd fraction, since 45 × 14 = 630,
42/45 = 42 × 14/45 × 14 = 588/630 - Subtract the two like fractions:
420/630 - 588/630 = 420 - 588/630 = -168/630 - After reducing the fraction, the answer is -4/15
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 56/42-42/45 28/42-84/45 28/84-42/45 28/42-42/90 84/42-42/45