Compare 21/30 and 75/90
21/30 is smaller than 75/90
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
21/30 = 21 × 3/30 × 3 = 63/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
75/90 = 75 × 1/90 × 1 = 75/90 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 63/90 < 75/90 or 21/30 < 75/90
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