Answer: The required probability is 25%.
Step-by-step explanation: Given that four books, one each on physics, chemistry, mathematics, and biology are about to be stacked on a shelf.
We are to find the probability that the mathematics book is on top if the books are stacked randomly.
Let, 'M' be the event that the topmost book is of mathematics.
Then, n(M)=1.
Let 'S' represents the sample space for the experiment.
Then, n(S) = 4.
Therefore, the probability that the mathematics book is on top is given by
Thus, the required probability is 25%.
Answer:
Answer D (the fourth one)
Step-by-step explanation:
First, we need to set up a (y−k)^2=4p(x−h). After plugging in all of your values, you would get (x-5)^2=-4(y-1). Now, we need to solve in terms of y by dividing each side by the factors that don't contain the variable. Your final solution should be
Answer:
The singers can finish first through fifth in 360360 ways.
Step-by-step explanation:
The order of the singers is important, because they are ranked by positions. So we use the permutations formula to solve this question.
Permutations formula:
The number of possible permutations of x elements from a set of n elements is given by the following formula:
In this question:
Top five singers, from 15 finalists. So
The singers can finish first through fifth in 360360 ways.