Results panel formatting...

I have the following code in Playgrounds:


var screenSizeInInches = ["iPhone 7" : 4.7, "iPhone 7 Plus" : 5.5, "iPad Pro" : 12.9]
print(screenSizeInInches["iPhone 7"])


This should display "4.7" in the results panel, instead it displays "Optional(4.7000000000000002)\n"


How do I set up Playground to just display the "4.7" ?