After you have consented to cookies by clicking on the "Accept" button, this web site will embed advertisement source code from Google Adsense,
an online advertising service of Google LLC ("Google") and you will see personalized advertisements by Google and their ad technology partners ( here a list ).
After accepting cookies this web site will also embed tracking source code from Google Analytics,
an online service of Google LLC ("Google") that tracks and reports website traffic. Our tracking code configuration has the 'anonymize IP address' option enabled.
Technically Internet cookies and third party cookies are then used to share information about your use of this web site with advertising providers who may combine it with other information that you have provided to them or that they’ve collected from your use of their services.
You may revoke your consent at any time using the "withdraw cookie consent" button at the end of each page.
If you do not want to accept cookies, sign up for a chargeable membershipplus.
Plus members can use this web site without ads, without tracking and without the need to accept third party cookies, because for them no advertising and no tracking service will be used.
or you can sign up for a membershipplus
Use our site without ad tracking and without advertising for
A box contains 9 balls marked 1 to 9. Four balls are drawn in succession without replacement. Determine the probability that the four-digit number formed is: a. even b. greater than 5000 c. an odd number less than 3000
a. Just look at the units digit to verify whether or not it's even. Essentially, it reduces the problem to the probability that the units digit is even. As such, the probability is just 4/9 (since there are 4 even numbers from 1-9)