Compare 21/42 and 18/7
1st number: 21/42, 2nd number: 2 4/7
21/42 is smaller than 18/7
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 7 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
21/42 = 21 × 1/42 × 1 = 21/42 - Likewise, for the 2nd fraction, since 7 × 6 = 42,
18/7 = 18 × 6/7 × 6 = 108/42 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 21/42 < 108/42 or 21/42 < 18/7
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