Compare 18/80 and 21/70
18/80 is smaller than 21/70
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 70 is 560
Next, find the equivalent fraction of both fractional numbers with denominator 560 - For the 1st fraction, since 80 × 7 = 560,
18/80 = 18 × 7/80 × 7 = 126/560 - Likewise, for the 2nd fraction, since 70 × 8 = 560,
21/70 = 21 × 8/70 × 8 = 168/560 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 126/560 < 168/560 or 18/80 < 21/70
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