A door lock consists of seven push buttons. If each "combination" consists of pushing three numbers at once and then two at once, and pushing the rest one by one. (a) How many possible codes are there? (b) If each code takes 3 seconds to try, what is the maximum length of time that it will take to get through the door?

Q: A professor gives his students 4 essay questions to prepare for an exam. Only 2 of the questions…

A:

Q: A student needs 8 more classes to complete her degree. If she has met 5 pre-requisites for all the…

A: A student needs 8 more classes to complete her degree. If she has met 5 pre-requisites for all the…

Q: A group of 5 students is to be chosen from a 30 student classroom. How many ways can this be done?

A: Note that here we have to select a group of 5 students from a 30 student classroom.

Q: Walter is creating a 5 digit code for an electronic lock. He can use any number, but cannot use the…

A:

Q: Apple decided to give an apple watch to the first person in line, an iPhone to the second person in…

A: From the given information, Apple decided to give apple product to all three persons who stand up in…

Q: A telephone number consists of 10 digits: 3 digit area code followed by 7 digit number. How many…

A: For area code , possible first digits are 1 to 9 and for the other number ,remaining digits are 0-9…

Q: If joe has 666666 snacks and aj has 2020 every time he comes over how many times will there be…

A: Let x denote the number of times aj can have cookies. So after x times, there will be no cookies…

Q: If Tim has 6 apples in each bag and he has 12 bags each, how many apples does he have all together?

A: Use unitary method.

Q: Joe, Megan, and Santana are salespeople. Their sales manager has 18 accounts and must assign six…

A:

Q: A professor gives his students 6 essay questions to prepare for an exam. Only 2 of the questions…

A: The objective of this question is to find out the number of different exams that are possible given…

Q: A license plate is to have the following form: three letters followed by three numbers. An example…

A: There are 26 letters (A-Z) and 10 numbers (0-9) We can pick each letter in 26 ways and we can pick…

Q: Professor Chauvet wants to know how quickly her students can type out a text message. So that…

A: The objective is to identify which of the given choices is best measure to describe the center of…

Q: How many days will it take Johan to read a 920-page book if he reads 20 pages the first day, 25…

A:

Q: A team plays 15 games a season. In how many ways can it have 8 wins and 7 losses?

A:

Q: Think of the image to the right as a bunch of Skittles candy. iPhone is ready to launch a new way to…

A: Given Information:  Total number of candies = 12 ( 2 each colour)  Number of candies to be selected…

Q: 1. The quadratic function f(x)= ax +bx+c is shown graphed below, where a, b, and c are known…

A:

Q: Twenty children are to be divided into an X team and a Y team of 10 each. The X team will play in…

A:

Q: A lock uses the letters A through H on the first dial and the digits 0 through 9 on the second and…

A:

Q: If sara walks her dog every 3 days, and marsha walks her dog every 2 days, at the end of 60 days,…

A:

Q: If there are 9 apples and my sister ate 3, how many apples are left?

A:

Q: A farmer knows that of every 50 eggs his chickens lay, only 45 will be marketable. If his chickens…

A: we have been given the information that  out of 50 eggs, only 45 are marketable