Compare 42/90 and 80/21
1st number: 42/90, 2nd number: 3 17/21
42/90 is smaller than 80/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
42/90 = 42 × 7/90 × 7 = 294/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
80/21 = 80 × 30/21 × 30 = 2400/630 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 294/630 < 2400/630 or 42/90 < 80/21
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