Compare 42/21 and 45/12
1st number: 2 0/21, 2nd number: 3 9/12
42/21 is smaller than 45/12
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
42/21 = 42 × 4/21 × 4 = 168/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
45/12 = 45 × 7/12 × 7 = 315/84 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 168/84 < 315/84 or 42/21 < 45/12
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