Subtract 42/12 from 40/90
1st number: 40/90, 2nd number: 3 6/12
40/90 - 42/12 is -55/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 12 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 90 × 2 = 180,
40/90 = 40 × 2/90 × 2 = 80/180 - Likewise, for the 2nd fraction, since 12 × 15 = 180,
42/12 = 42 × 15/12 × 15 = 630/180 - Subtract the two like fractions:
80/180 - 630/180 = 80 - 630/180 = -550/180 - After reducing the fraction, the answer is -55/18
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 80/90-42/12 40/90-84/12 40/90-42/24 40/90-42/36 40/90-42/60 40/90-42/84