Question

#1 What is the value of the expression 7–3?

Answers: A. –21 B. - 1/343 C.1/343 D. 343 

#2 What is the value of the expression 1/5^-5? Answers: A. 1/3125 B.1/25 C.25 D. 3125

 #3What is the value of the expression 2/4^-3?Answers: A. 1/32 B. 1/6 C.128 D.256  

#4  What value of k solves the equation? K^-2=1/64 Answers: A.1/8 B. 8 C. 32 D. 128

 #5 What value of n solves the equation? 4^N= 1/64   Answers: A. –3   B. 3   C. 16   D. 256

Answer 1

`\#1\ \ \ 7^(-3)= (1)/(7^3) = (1)/(343)\ \ \ \Rightarrow\ \ \ Ans.\ C\\ \\ \#2\ \ \ (1)/(5^(-5))=5^5=3125\ \ \ \Rightarrow\ \ \ \ Ans.\ D\\ \\ \#3\ \ \ (2)/(4^(-3))=2\cdot4^(3)=2\cdot 64=128\ \ \ \Rightarrow\ \ \ Ans.\ C\\ \\\#4\ \ \ K^(-2)= (1)/(64) \ \ \Rightarrow\ \ \ (1)/(K^2) = (1)/(64)\\\\ .\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ K^2=64 \ \ \Rightarrow\ \ K=8\ \ \Rightarrow\ \ Ans.\ B\\ \\`


`\#5\ \ \ 4^N= (1)/(64)\ \ \Rightarrow\ \ \ 4^N=4^(-3)\ \ \ \Rightarrow\ \ \ N=-3\ \ \ \Rightarrow\ \ \ Ans.\ A`

Answer 2

First question

The given expression is

`7^(-3)`

Which can also be written as

`(1)/(7^3)= (1)/(343)`

Therefore the correct option is C.

2.

The given expression is

`(1)/(5^(-5))`

Which can also be written as

`5^5 = 3125`

So the correct option is D

3.

The given expression is

`(2)/(4^(-3))`

Which can also be written as

`2*4^3 = 2* 64=128`

And the correct option is C

4.

The given equation is

`k^(-2) = (1)/(64) \\ k^2 = 64 \\ k^2 = 8^2 \\ k=8`

So the correct option is B

5.

The given equation is

`4^N = (1)/(64) \\ 4^N = 4^(-3) \\ N =-3`

And the correct option is A .