Compare 40/84 and 18/21
40/84 is smaller than 18/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
40/84 = 40 × 1/84 × 1 = 40/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
18/21 = 18 × 4/21 × 4 = 72/84 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 40/84 < 72/84 or 40/84 < 18/21
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