powershell help

I am new to Powershell and am stuck on a script I need to do using parameter(). Here is the question:

This script will take the user’s name and 3 separate grades. It will then average the
grades and print the result. This script should do the following:

  1. Using the param() function, accept 4 command-line inputs to the script and name
    them $name, $test1, $test2, $test3.
  2. Calculate the average grade and set it equal to a variable called $average
  3. Print the message “The test average for name is average”. Use interpolation to
    print the actual name and numeric average in the message.
  4. Test the script a few times with different data


param($name,$test1,$test2,$test3) $average = $test1 + $test2 + $test3 / 3 write "Grade for $name is $average"