Compare 20/40 and 81/90
20/40 is smaller than 81/90
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 90 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
20/40 = 20 × 9/40 × 9 = 180/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
81/90 = 81 × 4/90 × 4 = 324/360 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 180/360 < 324/360 or 20/40 < 81/90
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