Compare 21/84 and 18/70
21/84 is smaller than 18/70
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 70 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Likewise, for the 2nd fraction, since 70 × 6 = 420,
18/70 = 18 × 6/70 × 6 = 108/420 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 105/420 < 108/420 or 21/84 < 18/70
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