Compare 5/20 and 18/21
5/20 is smaller than 18/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
5/20 = 5 × 21/20 × 21 = 105/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
18/21 = 18 × 20/21 × 20 = 360/420 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 105/420 < 360/420 or 5/20 < 18/21
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