Question

multiply.
3.57
× 7.8

Explanation:

Step1: Multiply as integers

First, ignore the decimal points and multiply 357 by 78.
\[

$$\begin{align*} 357\times78&=357\times(70 + 8)\\ &=357\times70+357\times8\\ &=24990 + 2856\\ &=27846 \end{align*}$$

\]

Step2: Count decimal places

The number \(3.57\) has 2 decimal places and \(7.8\) has 1 decimal place. So in total, there are \(2 + 1=3\) decimal places.

Step3: Place the decimal point

Now, place the decimal point in the product \(27846\) such that there are 3 decimal places. So we get \(27.846\).

Answer:

\(27.846\)