Step-1: Factorize the numerator & denominator. Identify the common factors on the top and bottom. Cancel the common factors to get the lowest form of a fraction.
618×5418=2×32×3×3×2×3×3×32×3×3
=13×3
=13×31
Step-2: Multiply the numerators and denominators.
=1×33×1
=33
=1