Compare 21/30 and 28/42
21/30 is greater than 28/42
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
21/30 = 21 × 7/30 × 7 = 147/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
28/42 = 28 × 5/42 × 5 = 140/210 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 147/210 > 140/210 or 21/30 > 28/42
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