Compare 21/30 and 42/40
1st number: 21/30, 2nd number: 1 2/40
21/30 is smaller than 42/40
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 30 × 4 = 120,
21/30 = 21 × 4/30 × 4 = 84/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
42/40 = 42 × 3/40 × 3 = 126/120 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 84/120 < 126/120 or 21/30 < 42/40
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/30 and 42/40 21/30 and 84/40 21/60 and 42/40 21/30 and 42/80 63/30 and 42/40 21/90 and 42/40