Natalie can take one of her three friends with her on a trip to Italy. She can't decide whom to take. Nick suggests that Natalie use a random number generator to assign numbers 1 through 20 to him, Sarah, and Mike until all the numbers are used. Then Natalie can pick a number from 1 to 20, and that friend will go. Is Nick's suggestion fair? Explain.

\begin{tabular}{|c|c|}
\hline
Friend & Assigned Number \\
\hline
Nick & \\
\hline
Sarah & \\
\hline
Mike & \\
\hline
\end{tabular}

Assign a Number [tex]$\square$[/tex]



Answer :

Let's analyze Nick's suggestion step by step.

1. Total Numbers to Assign: There are 20 numbers available, ranging from 1 to 20.

2. Number of Friends: There are 3 friends - Nick, Sarah, and Mike.

3. Numbers Per Friend: To check how many numbers each friend will get, we divide the total numbers by the number of friends:
[tex]\[ \text{Numbers assigned to each friend} = \frac{20}{3} \approx 6.67 \][/tex]

This resulting number indicates that each friend would theoretically get around 6.67 numbers.

4. Fairness of Assignment:
- For the assignment of numbers to be fair, each friend must receive an equal number of integers.
- Since the division of 20 by 3 results in a non-integer (6.67), we cannot divide the 20 numbers into three equal integer parts.

Thus, the distribution of numbers would look like this:
[tex]\[ \begin{tabular}{|c|c|} \hline Friend & Assigned Numbers \\ \hline Nick & 6 or 7 numbers \\ \hline Sarah & 6 or 7 numbers \\ \hline Mike & 6 or 7 numbers \\ \hline \end{tabular} \][/tex]

One or more friends will inevitably end up with 7 numbers while the others will have 6. As it's impossible to assign exactly 6.67 numbers per friend, this discrepancy makes the process unfair.

When Natalie selects a number from 1 to 20, the friend with 7 numbers is more likely to be chosen than the friends with 6 numbers. Hence, Nick's suggestion is not fair because the allocation of numbers is not equal.

The true result:
[tex]\[ (6.666666666666667, \text{False}) \][/tex]

indicates that the exact division is approximately 6.67 per friend and that achieving a fair division is not possible. Therefore, Nick's suggestion to use a random number generator to assign numbers is unfair.