Compare 10/21 and 9/15
10/21 is smaller than 9/15
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
10/21 = 10 × 5/21 × 5 = 50/105 - Likewise, for the 2nd fraction, since 15 × 7 = 105,
9/15 = 9 × 7/15 × 7 = 63/105 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 50/105 < 63/105 or 10/21 < 9/15
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