round 0.9998 to 3 decimal places

Question

anonymous · Answer

....really?

theeric · Answer

Well,
$0.9998$
$\ \ \uparrow\uparrow\uparrow$
$\ \ 1\ 2\ 3$
So, we look at the next digit. If it is less than 5, we just cut the rest off. If it is 5 or greater than 5, we round that 3$^{rd}$ digit up and then cut the rest off.

$8$ is greater than $5$, so we round up.

$0.9998$
$~~~~~~\uparrow$this one goes up to $10$.

But we can't have a "10" in one digit. 10 thousandths is 1 hundredth and 0 thousandths, so 0.010 is replacing that 0.009.

So
$0.9998$
$~~~~~~\uparrow\uparrow$ subtract these away
add $.010$ to replace that.

$\ \ \ \ \ 0.9998\-0.0098\\underline{+\ \ 0.010\ }$

anonymous · Answer

so if it was 4 decimal places it would be 0.001 right

theeric · Answer

Now we have the same issue! The pattern is this. When you add 1 to a 9, you make that digit be 0, and add 1 to the digit to the left.

You had to do this a few times to get to your answer.

Well, there are only three decimal places in that number. If it asked you to round to 4, you wouldn't actually be rounding at all, so you can't do it..

anonymous · Answer

ok wat if its this 0.99987 round to 4 ..@theEric

theeric · Answer

Then you cut off the 7, and replace the 8 with one greater, a 9. So it would be 0.9999.

anonymous · Answer

oh ok..thank u very much

theeric · Answer

You're welcome! Any more questions?

anonymous · Answer

i have a venn diagram question ..i dont know if you can help tho..