Compare 21/18 and 45/30
1st number: 1 3/18, 2nd number: 1 15/30
21/18 is smaller than 45/30
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 30 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 18 × 5 = 90,
21/18 = 21 × 5/18 × 5 = 105/90 - Likewise, for the 2nd fraction, since 30 × 3 = 90,
45/30 = 45 × 3/30 × 3 = 135/90 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 105/90 < 135/90 or 21/18 < 45/30
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