What is the front end estimation to subtract 189 from 643?

Answer 1

Oh, dude, front end estimation is like when you round numbers to make math easier, right? So, if you wanna subtract 189 from 643 using front end estimation, you could round 643 to 600 and 189 to 200, then subtract 200 from 600 to get 400. But like, who needs estimation when you can just do the actual math, am I right?

Answer 2

Front End Estimation can be confusing before you understand it. There are two simple steps for front end estimation: add the digits of the two highest place values, insert zeros for the other place values. Now let's put that into us for your question!

189-643 =

(1 & 8 are the first two digits for 189 ... 6 & 4 are the first two digits for 643)

18_ - 64_ =

(Fill in zeros for the place values you have emptied)

180-640= -460

-460