Compare 21/45 and 12/30
21/45 is greater than 12/30
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 30 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 45 × 2 = 90,
21/45 = 21 × 2/45 × 2 = 42/90 - Likewise, for the 2nd fraction, since 30 × 3 = 90,
12/30 = 12 × 3/30 × 3 = 36/90 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 42/90 > 36/90 or 21/45 > 12/30
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