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Problem #87 · October 22, 2026

EKUB — greatest common divisor and EKUK — least common multiple

Reduce the fraction 84126\frac{84}{126} to an irreducible form.
  1. A23\frac{2}{3}
  2. B32\frac{3}{2}
  3. C69\frac{6}{9}
  4. D1421\frac{14}{21}
  5. E46\frac{4}{6}

WORKED EXAMPLE

Solution

Let us find EKUB(84;126)EKUB(84; 126): 84=22⋅3⋅784 = 2^2 \cdot 3 \cdot 7, 126=2⋅32⋅7126 = 2 \cdot 3^2 \cdot 7, so EKUB =2⋅3⋅7=42= 2 \cdot 3 \cdot 7 = 42. We divide the numerator and the denominator by 42: 84:42126:42=23\frac{84 : 42}{126 : 42} = \frac{2}{3}.
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