Question

unit 8 summative
the number 345,000,000 in scientific notation is?
34.5 x 10^12
3.45 x 10^8
345.0 x 10^11
3.45 x 10^11

Explanation:

Step1: Define scientific notation rule

Scientific notation is written as $a \times 10^n$, where $1 \leq a < 10$ and $n$ is an integer.

Step2: Adjust 345,000,000,000 to fit $a$

Move the decimal point 11 places left to get $a=3.45$.

Step3: Determine exponent $n$

Since we moved 11 places left, $n=11$.

Step4: Match to options

The expression is $3.45 \times 10^{11}$, which matches the last option.

Answer:

D. 3.45 x 10^11