Compare 15/18 and 21/42
15/18 is greater than 21/42
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 42 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
15/18 = 15 × 7/18 × 7 = 105/126 - Likewise, for the 2nd fraction, since 42 × 3 = 126,
21/42 = 21 × 3/42 × 3 = 63/126 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 105/126 > 63/126 or 15/18 > 21/42
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