Compare 21/45 and 40/21
1st number: 21/45, 2nd number: 1 19/21
21/45 is smaller than 40/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 21 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 45 × 7 = 315,
21/45 = 21 × 7/45 × 7 = 147/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
40/21 = 40 × 15/21 × 15 = 600/315 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 147/315 < 600/315 or 21/45 < 40/21
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