Compare 30/15 and 40/21
1st number: 2 0/15, 2nd number: 1 19/21
30/15 is greater than 40/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
30/15 = 30 × 7/15 × 7 = 210/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
40/21 = 40 × 5/21 × 5 = 200/105 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 210/105 > 200/105 or 30/15 > 40/21
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