Subtract 30/40 from 42/7
1st number: 6 0/7, 2nd number: 30/40
42/7 - 30/40 is 21/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 7 × 40 = 280,
42/7 = 42 × 40/7 × 40 = 1680/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
30/40 = 30 × 7/40 × 7 = 210/280 - Subtract the two like fractions:
1680/280 - 210/280 = 1680 - 210/280 = 1470/280 - After reducing the fraction, the answer is 21/4
- In mixed form: 51/4
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/7-30/40 42/7-60/40 42/14-30/40 42/7-30/80 42/7-90/40 42/21-30/40 42/35-30/40 42/49-30/40