The total number of combinations available to just pick 1 t-shirt is 20
Explanation:
Given:
4 different sizes of t-shirts are available
5 different colors of t-shirt are available
Different outcomes if the t-shirts have to be picked one by one:
Different outcomes = 4! + 5!
= 24 + 120
= 144
Number of combinations available to just pick 1 t-shirt is:
Number of combinations = 4 X 5
= 20
Therefore, the total number of combinations available to just pick 1 t-shirt is 20