Compare 42/80 and 28/21
1st number: 42/80, 2nd number: 1 7/21
42/80 is smaller than 28/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 21 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 80 × 21 = 1680,
42/80 = 42 × 21/80 × 21 = 882/1680 - Likewise, for the 2nd fraction, since 21 × 80 = 1680,
28/21 = 28 × 80/21 × 80 = 2240/1680 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 882/1680 < 2240/1680 or 42/80 < 28/21
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