Compare 45/70 and 15/21
45/70 is smaller than 15/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
45/70 = 45 × 3/70 × 3 = 135/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
15/21 = 15 × 10/21 × 10 = 150/210 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 135/210 < 150/210 or 45/70 < 15/21
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