Subtract 21/42 from 45/4
1st number: 11 1/4, 2nd number: 21/42
45/4 - 21/42 is 43/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 42 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 4 × 21 = 84,
45/4 = 45 × 21/4 × 21 = 945/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
21/42 = 21 × 2/42 × 2 = 42/84 - Subtract the two like fractions:
945/84 - 42/84 = 945 - 42/84 = 903/84 - After reducing the fraction, the answer is 43/4
- In mixed form: 103/4
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/4-21/42 45/8-21/42 45/4-21/84 45/4-63/42 45/12-21/42 45/20-21/42 45/28-21/42