Compare 18/45 and 28/21
1st number: 18/45, 2nd number: 1 7/21
18/45 is smaller than 28/21
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,
18/45 = 18 × 7/45 × 7 = 126/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
28/21 = 28 × 15/21 × 15 = 420/315 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 126/315 < 420/315 or 18/45 < 28/21
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