Compare 21/30 and 18/45
21/30 is greater than 18/45
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 45 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
21/30 = 21 × 3/30 × 3 = 63/90 - Likewise, for the 2nd fraction, since 45 × 2 = 90,
18/45 = 18 × 2/45 × 2 = 36/90 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 63/90 > 36/90 or 21/30 > 18/45
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