Compare 12/40 and 21/45
12/40 is smaller than 21/45
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 45 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
12/40 = 12 × 9/40 × 9 = 108/360 - Likewise, for the 2nd fraction, since 45 × 8 = 360,
21/45 = 21 × 8/45 × 8 = 168/360 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 108/360 < 168/360 or 12/40 < 21/45
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