Compare 20/70 and 21/90
20/70 is greater than 21/90
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
20/70 = 20 × 9/70 × 9 = 180/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
21/90 = 21 × 7/90 × 7 = 147/630 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 180/630 > 147/630 or 20/70 > 21/90
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