Compare 20/21 and 4/90
20/21 is greater than 4/90
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,
20/21 = 20 × 30/21 × 30 = 600/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
4/90 = 4 × 7/90 × 7 = 28/630 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 600/630 > 28/630 or 20/21 > 4/90
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