Subtract 80/72 from 42/40
1st number: 1 2/40, 2nd number: 1 8/72
42/40 - 80/72 is -11/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
42/40 = 42 × 9/40 × 9 = 378/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
80/72 = 80 × 5/72 × 5 = 400/360 - Subtract the two like fractions:
378/360 - 400/360 = 378 - 400/360 = -22/360 - After reducing the fraction, the answer is -11/180
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/40-80/72 42/80-80/72