Description: Sal uses place value and decomposing numbers to subtract decimals to the tenths place, such as 2 - 1.2. So let's say we wanna figure out what two minus 1.2 is. One way is you could say, "Look, this is the same thing "as two minus one "minus 2/10." This is two minus one and 2/10.*Teacher Advisor is 100% free.