If the number cube is rolled 18 times, then the number of unsuccessful rolls = 90 unsuccessful rolls.
<u>Step-by-step explanation</u>:
<u>step 1</u>: A cube has six faces and each face is numbered from 1 to 6.
<u>step 2</u>: The win in the game requires the number 6, when a cube is rolled.
<u>step 3</u>: On rolling a cube, the outcomes are (1,2,3,4,5, and 6).
<u>step 4</u>: Out of these outcomes, 5 are unsuccessful rolls (1,2,3,4,5) and 1 is a successful roll (6).
<u>step 5</u>: If the cube is rolled 18 times,
then the number of unsuccessful rolls = 18 * 5 unsuccessful rolls
= 90 unsuccessful rolls.
