How many centimeters is it from the pitchers mound to home plate

I don't know.

But if you can find the number of FEET from the mound to
home plate, then you can multiply it by these 2 fractions and
convert that into centimeters.

         (12 inches / 1 foot)
and
         (2.54 centimeters / inch) . 
        
Usually, you can't just go multiplying numbers by other things without
changing the value of the number. 

But if you look at these two fractions, you'll see that each of them is
actually equal to ' 1 ' ... the numerator is equal to the denominator. 

So when you multiply a number by these fractions, you're just multiplying
it by ' 1 ' twice.  Its value doesn't change, but its units do !  And that's exactly
what you need.