Compare 30/40 and 72/21
1st number: 30/40, 2nd number: 3 9/21
30/40 is smaller than 72/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
30/40 = 30 × 21/40 × 21 = 630/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
72/21 = 72 × 40/21 × 40 = 2880/840 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 630/840 < 2880/840 or 30/40 < 72/21
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