Subtract 90/50 from 42/45
1st number: 42/45, 2nd number: 1 40/50
42/45 - 90/50 is -13/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 50 is 450
Next, find the equivalent fraction of both fractional numbers with denominator 450 - For the 1st fraction, since 45 × 10 = 450,
42/45 = 42 × 10/45 × 10 = 420/450 - Likewise, for the 2nd fraction, since 50 × 9 = 450,
90/50 = 90 × 9/50 × 9 = 810/450 - Subtract the two like fractions:
420/450 - 810/450 = 420 - 810/450 = -390/450 - After reducing the fraction, the answer is -13/15
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/45-90/50 42/90-90/50