Compare 21/90 and 7/20
21/90 is smaller than 7/20
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 90 × 2 = 180,
21/90 = 21 × 2/90 × 2 = 42/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
7/20 = 7 × 9/20 × 9 = 63/180 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 42/180 < 63/180 or 21/90 < 7/20
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