Compare 21/70 and 90/72
1st number: 21/70, 2nd number: 1 18/72
21/70 is smaller than 90/72
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 72 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 70 × 36 = 2520,
21/70 = 21 × 36/70 × 36 = 756/2520 - Likewise, for the 2nd fraction, since 72 × 35 = 2520,
90/72 = 90 × 35/72 × 35 = 3150/2520 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 756/2520 < 3150/2520 or 21/70 < 90/72
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