Compare 21/45 and 15/40
21/45 is greater than 15/40
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 45 × 8 = 360,
21/45 = 21 × 8/45 × 8 = 168/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
15/40 = 15 × 9/40 × 9 = 135/360 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 168/360 > 135/360 or 21/45 > 15/40
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