Compare 21/45 and 16/18
21/45 is smaller than 16/18
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 18 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 18 × 5 = 90,
16/18 = 16 × 5/18 × 5 = 80/90 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 42/90 < 80/90 or 21/45 < 16/18
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