Subtract 60/42 from 30/90
1st number: 30/90, 2nd number: 1 18/42
30/90 - 60/42 is -23/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 42 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
30/90 = 30 × 7/90 × 7 = 210/630 - Likewise, for the 2nd fraction, since 42 × 15 = 630,
60/42 = 60 × 15/42 × 15 = 900/630 - Subtract the two like fractions:
210/630 - 900/630 = 210 - 900/630 = -690/630 - After reducing the fraction, the answer is -23/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 60/90-60/42 30/90-60/84