Question

Without calculating, is the equation (1.8 times 3) times 2.1 = ( 1.8 times 2.1 ) true or false? Explain your reasoning.

Answer 1

It is true due to the commutative property of multiplication. If all of your operations are multiplication, then the integers can move around and you can still get the same answer. 
^This is only true if you meant to type (1.8x3)x2.1=(1.8x2.1)x3

If you meant what you typed, then the equation is false. The left side would be 3 times the value of the right side due to the 3 being on the left side and not the right side while without the 3 the two sides would be equal.