Subtract 42/40 from 30/45
1st number: 30/45, 2nd number: 1 2/40
30/45 - 42/40 is -23/60.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 45 × 8 = 360,
30/45 = 30 × 8/45 × 8 = 240/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
42/40 = 42 × 9/40 × 9 = 378/360 - Subtract the two like fractions:
240/360 - 378/360 = 240 - 378/360 = -138/360 - After reducing the fraction, the answer is -23/60
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 60/45-42/40 30/45-84/40 30/90-42/40 30/45-42/80 90/45-42/40