Compare 18/21 and 90/45
1st number: 18/21, 2nd number: 2 0/45
18/21 is smaller than 90/45
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 21 × 15 = 315,
18/21 = 18 × 15/21 × 15 = 270/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
90/45 = 90 × 7/45 × 7 = 630/315 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 270/315 < 630/315 or 18/21 < 90/45
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