Compare 21/45 and 42/40
1st number: 21/45, 2nd number: 1 2/40
21/45 is smaller than 42/40
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,
42/40 = 42 × 9/40 × 9 = 378/360 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 168/360 < 378/360 or 21/45 < 42/40
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