Compare 7/21 and 70/90
7/21 is smaller than 70/90
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 21 × 30 = 630,
7/21 = 7 × 30/21 × 30 = 210/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
70/90 = 70 × 7/90 × 7 = 490/630 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 210/630 < 490/630 or 7/21 < 70/90
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