When rounding a value to the nearest hundred thousandth, look at the digit in the column to the right, the millionths.
0.00002, 2* 10^(- 5)
Practice makes perfect
We want to round the following value to the nearest hundred thousandth. Then we will rewrite the outcome as a single digit times a power of ten. Let's do it!
0.00002468
Rounding
Let's take a look at the digit in the column to the right, the millionths.
0.00002468
The number in the column is 4. Now, recall the rule for rounding.
If the number is 5 or more, round up.
If the number is 4 or less, round down.
This means we will be rounding down. Let's do that!
0.00002468 ≈ 0.00002
We can fill in the first blank.
Rounded to the nearest hundred thousandth, the number is about 0.00002.
Rewriting
Now we want to rewrite the estimate as a product of a single digit and a power of ten. Let's take a look.
0.00002
For that, we will rewrite the number as its greatest place value times a power of 10. To find the exponent, we need to count the zeros in the number.
0.00002
We see that there are 5 zeros in the number. Now, recall how the sign of the exponent changes for different numbers.
Numbers Greater Than 1
Numbers Less Than 1
positive (+)
negative (-)
Since the number is less than 1, the exponent is negative. This means that the exponent of 10 is - 5. We now have everything we need to rewrite our number.
0.00002 = 2* 10^(- 5)
We can now fill in the finas two blanks.
Written as a single digit times a power of ten, the estimate is \boxed{2}\times 10^\boxed{\text{-} 5}.
