100 Primes

Middle School Madness - April 22, 2019


100 Primes Image

You are given the first 100 prime numbers greater than zero.  If you multiplied these 100 prime numbers together, what would be the units (ones) digit of the product of these 100 prime numbers?

Submit answer

Immediately after your correct answer is submitted, your name will be posted here.

NOTE: Anyone can answer Middle School Madness questions, but only participants 15 years of age or younger will be awarded points and displayed in the rankings.

Past problems
Individual Monthly & Annual Rankings
Leaderboard Monthly & Annual Rankings

Custom Leaderboards Are Here!

Take the competition to the next level and encourage participation by creating custom leaderboards for your students or friends to join. Click below to try it out now!

Get Started with Custom Leaderboards

Need Scratch Paper?

We encourage you to use Casio's new free online math software, ClassPad.net, as your digital scratch paper while solving the problems on our site!

Use ClassPad for digital scratch paper to solve this problem!