Question

8
Multiply and write your answer in scientific notation. Click Here for Help Video.



Be sure to write your answer with the multiplication
×
×





(
7
×
1
0
−
2
)
(7×10
−2
) ·
(
4
×
1
0
9
)
(4×10
9
)

Answer 1

To multiply the two numbers in scientific notation, you can use the following steps:

\[
(a \times 10^m) \times (b \times 10^n) = (a \times b) \times 10^{m+n}
\]

In your case, you are multiplying:

\[
(7 \times 10^{-2}) \times (4 \times 10^{9})
\]

First, multiply the coefficients (the numbers in front):

\[
7 \times 4 = 28
\]

Next, add the exponents:

\[
-2 + 9 = 7
\]

Putting it all together, we have:

\[
28 \times 10^{7}
\]

Now we need to express 28 in proper scientific notation. We can rewrite 28 as:

\[
2.8 \times 10^1
\]

So, substituting this back in gives:

\[
(2.8 \times 10^1) \times 10^7 = 2.8 \times 10^{1 + 7} = 2.8 \times 10^8
\]

Thus, the final answer in scientific notation is:

\[
\boxed{2.8 \times 10^8}
\]