Compare 12/21 and 45/40
1st number: 12/21, 2nd number: 1 5/40
12/21 is smaller than 45/40
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
12/21 = 12 × 40/21 × 40 = 480/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
45/40 = 45 × 21/40 × 21 = 945/840 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 480/840 < 945/840 or 12/21 < 45/40
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