Compare 21/45 and 12/42
21/45 is greater than 12/42
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 42 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 45 × 14 = 630,
21/45 = 21 × 14/45 × 14 = 294/630 - Likewise, for the 2nd fraction, since 42 × 15 = 630,
12/42 = 12 × 15/42 × 15 = 180/630 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 294/630 > 180/630 or 21/45 > 12/42
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