# Where would you place the decimal point in this product? 9.412 multiplied by 100=9412

## This is a multiple choice question and the alternatives are as follows a. 9.41200 b. .09412 c.94.12 d.941.2

Nov 25, 2017

You can often place decimal points by using logic.

#### Explanation:

The math problem was approximately

$9 \times 100$

So the logical answer has to be around 900.

-- not 90 or 9000.

d. 941.2
.......................

If you can't estimate exactly enough, here is a plan that always works:

Count the total number of decimal places of both numbers in the original question.

2) Then look at the answer
Starting on the right of the answer, and counting backwards to the left, count off the same number of places.

3) That will always be where the decimal point goes.
................

Example:
Multiply $2.16 \times 14.328$
$3094848$

To locate the decimal point, start at the question.
Count the TWO decimal places in $2.16$ plus the THREE decimal places in $14.328 .$

That is a total of five decimal places.

$30.94848$
The original problem is roughly $2 \times 14$, so you want the answer to be around 28, not 2 or 280.