The orders are 1 stay the same. 2 change to 4, 3 change to 2, 4 change to 3, and 5 stays the same.
Multiple: 1/ 8 & 2/ 4 = 1 · 2/ 8 · 4 = 2/ 32 = 1 · 2/ 16 · 2 = 1/ 16 Multiply both numerators and denominators. Result fraction keep to lowest possible denominator (lowest=2). In the next intermediate step , cancel by a common factor of 2 gives 1/ 16 . In words - one eighth multiplied by two quarters = one sixteenth.
Final result: 1/16