Compare 18/45 and 21/90
18/45 is greater than 21/90
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 45 × 2 = 90,
18/45 = 18 × 2/45 × 2 = 36/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
21/90 = 21 × 1/90 × 1 = 21/90 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 36/90 > 21/90 or 18/45 > 21/90
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