Respuesta :
Answer:
Mary simplified an expression. [tex]1.29 \times 10^{5}[/tex] is correct representation in scientific notation.
Solution:
Given that Mary simplified an expression and got [tex]12.9 \times 10^{4}[/tex] for answer in scientific notation.
According to Angela, answer is incorrect. Need to find reason why Angela consider [tex]12.9 \times 10^{4}[/tex] as incorrect scientific notation and find the correct answer.
Let’s understand what is scientific notation of any number.
Scientific notation is a way of representing number between 1 and 10 including 1 and excluding 10 multiplied by appropriate power of 10.
According to Mary’s simplification the number she is getting is 12.9 but in scientific notation, number must be in between 1 to 10
So [tex]12.9 \times 10^{4}[/tex] is not correct scientific notation.
[tex]\text { Let's rewrite } 12.9 \times 10^{4} \text { as } 1.29 \times 10^{1} \times 10^{4}=1.29 \times 10^{5}[/tex]
Now we got 1.29 which is in between 1 and 10 multiplied by [tex]10^5[/tex]
Hence [tex]1.29 \times 10^{5}[/tex] is correct representation in scientific notation.
