Final answer:
To show the value of the variable numdogs on the screen, you can use a print() function in Python after obtaining the value from user input through the input() function.
Step-by-step explanation:
To output the value of the variable numdogs entered by a user, we can write a simple code snippet in various programming languages. However, as the language is not specified in the question, here's an example in Python:
numdogs = int(input('Enter the number of dogs: '))
print(numdogs)
When the program runs, it will ask the user to "Enter the number of dogs: ". After the user inputs a number, that number will be assigned to the variable numdogs, and then the print() function will output the value of numdogs, followed by a newline character.