If you roll a standard number cube 42 times, how many times do you expect the cube to show a six or an eight?

When a nursery owner orders plants from the distributor, 92% of the plants arrive alive. If the nursery owner wants their inventory of a particular plant to be 540 living plants, how many plants should the owner order?

Please help

Respuesta :

Number 1: First of all: You can expect it to roll a 6 7 times. Why? If you roll a cube 42 times, and there are 6 possible outcomes, the theoretical probability of rolling each number is rolling it 7 times. 

Number 2: take 92/100 and compare it to 540/?
Divide 540 by 100, and you get 5.4 . Then, multiply 5.4 by 92, and then you get 496.8. If they want at least 92% alive, they should order at least 497 plants.