Compare 18/70 and 42/21
1st number: 18/70, 2nd number: 2 0/21
18/70 is smaller than 42/21
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,
18/70 = 18 × 3/70 × 3 = 54/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
42/21 = 42 × 10/21 × 10 = 420/210 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 54/210 < 420/210 or 18/70 < 42/21
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