The below given figure comprises of a pattern through which you can determine the missing letter. Can you push your mind to find the pattern and add the missing letter?
Christina makes tasty toast in a small pan. After toasting one side of a slice, she turns it over. Each side takes 30 seconds. The pan can only hold two slices.
How can she toast both sides of three slices in 1 & 1/2 instead of 2 minutes?