No. We claim that

and use algebra to prove the statement.
Let

. Multiply this by ten to get

. Subtract the initial equation to give

and divide by

to see that

. Substituting into the original equation gives

, proving the desired statement.
I cannot understand what you are saying
D has the commutative property because it just flip flopped the numbers.
Goldfish: 4*0.50=2 so $2.00
Goldfish: 7*0.70=4.90
4.90.2.00=$6.90
Forget the '34' part of 8:34 and the '18' minutes from 3 hours and 18 minutes for now.
Just add 3 hours on to 8, to get 11. Then, bring back the 34 and 18 and add them together. 34 + 12 = 52. Now put that 52 on the end of the 11, and you get 11:52 as the end time.