Compare 4/21 and 21/42
421 is smaller than 2142
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
421 = 4 × 221 × 2 = 842 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
2142 = 21 × 142 × 1 = 2142 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 842 < 2142 or 421 < 2142
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