Compare 21/40 and 25/30
21/40 is smaller than 25/30
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 30 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 40 × 3 = 120,
21/40 = 21 × 3/40 × 3 = 63/120 - Likewise, for the 2nd fraction, since 30 × 4 = 120,
25/30 = 25 × 4/30 × 4 = 100/120 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 63/120 < 100/120 or 21/40 < 25/30
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