In how many ways can 7 people be lined up to see a movie if Ben must be at the start of the line?
is the answer 720?
To calculate the number of ways to line up 7 people, with the condition that Ben must be at the start of the line, we can consider Ben as fixed at the first position. We then need to arrange the remaining 6 people in the remaining 6 positions.
The number of ways to arrange 6 people in 6 positions can be calculated using the concept of factorial. The factorial of a number is denoted by the exclamation mark (!) and represents the product of all positive integers up to that number.
In this case, we need to find the factorial of 6, which can be written as 6! = 6 x 5 x 4 x 3 x 2 x 1 = 720.
Therefore, the answer is indeed 720.