License Plates, Codes and Passwords
Written by Adi Ackerman, Head Teacher
"License Plates, Codes and Passwords" is written for 8th Grade (Ages 13-14). A 7th grader who is already steady on probability can use it too, and an older student can use it as a short review.
8th grade math worksheet: count license plates, PINs, passwords and lock codes with the counting principle, with and without repeats. Answer key included. Part of our counting principle probability collection.
How do I use this worksheet?
Assign Use the Counting Principle first, then the sheet with three or more choices. Assign the license plate sheet for a challenge and the riddle as a review.
What students will practice
- Students will use the counting principle to count license plates, PINs and passwords.
- Students will count codes when digits or letters can repeat.
- Students will count codes when no digit or letter is used twice.
Curriculum Links
Find this in the curriculum
Browse the grade, subject, and topic this belongs to.
FAQ
How do I use this counting principle worksheet?
⌄
Assign Use the Counting Principle first, then the sheet with three or more choices. Assign the license plate sheet for a challenge and the riddle as a review.
What does this worksheet teach?
⌄
Count license plates, PINs, passwords and lock codes with the counting principle, with and without repeats. The directions on the page read: Use the counting principle. Show the product in the box and write the total on the line. The page opens with a worked example, and an answer key is included.
Can I use this counting principle worksheet for homeschool or classroom?
⌄
Yes, both. We made it for 8th grade probability, and it works the same at home or at school. At home, a student can work through it alone and then go over it with you, which shows quickly what is solid and what needs another look. In class it works as independent practice, homework or a warm-up, and you can print one copy or a full set.
How does the counting principle work?
⌄
Multiply the number of choices for each step. With 6 hats and 7 scarves there are 6 times 7, or 42 outfits.
How do you count codes when no digit repeats?
⌄
Each step has one fewer choice than the step before. A 3-digit code from 1 to 9 with no digit twice has 9 times 8 times 7, or 504 codes.
Does the counting principle match a tree diagram?
⌄
Yes. The number of outcomes at the bottom of a tree equals the product of the choices. The Counting Principle vs Tree Diagram sheet has students check that both answers match.
Are answer keys included for these sheets?
⌄
Yes. Each of the 5 counting principle sheets comes with an answer key.
Ratings & Reviews
No reviews yet. Be the first to share what you think.
Reviews are for ClassWeekly members.
Make a Request
Spotted something to fix, or want a worksheet we don't have yet? Tell us and we'll make it.
Worksheet Details
| Grade | 8th Grade |
| Subject | Math |
| Topic | Probability |
| Pages | 1 page |
| Difficulty | Medium |
What is ClassWeekly?
ClassWeekly offers free worksheets and printable learning resources for kids, from preschool up. All worksheets are aligned to Common Core, NGSS, and C3 Framework standards and designed by educators. Become a member to access the full library and download unlimited PDFs.