Evaluate the expression for m=4 n=5 p=-2
mn^p
The Correct Answer and Explanation is:
To evaluate the expression ( mn^p ) for the given values ( m = 4 ), ( n = 5 ), and ( p = -2 ), we start by substituting the values into the expression:
[
mn^p = 4 \cdot 5^{-2}
]
Next, we need to calculate ( 5^{-2} ). The negative exponent indicates that we take the reciprocal of the base raised to the positive of the exponent:
[
5^{-2} = \frac{1}{5^2}
]
Calculating ( 5^2 ):
[
5^2 = 25
]
Thus, we can rewrite ( 5^{-2} ) as:
[
5^{-2} = \frac{1}{25}
]
Now we substitute this back into the expression:
[
mn^p = 4 \cdot \frac{1}{25}
]
Now, we can multiply:
[
mn^p = \frac{4}{25}
]
So the final evaluated expression for ( mn^p ) is:
[
\frac{4}{25}
]
Explanation:
In evaluating expressions that involve variables and exponents, it’s crucial to follow the order of operations and the rules governing exponents. Here, we first substituted the given values of ( m ), ( n ), and ( p ) into the expression ( mn^p ). The expression features a multiplication of ( m ) with ( n ) raised to the power of ( p ).
When dealing with negative exponents, it’s essential to remember that a negative exponent denotes the reciprocal of the base raised to the absolute value of the exponent. Therefore, ( 5^{-2} ) translates into ( \frac{1}{5^2} ). This interpretation allows us to simplify the expression further.
After substituting the value of ( 5^{-2} ) back into the expression, we then proceeded with straightforward multiplication, yielding the result ( \frac{4}{25} ). This result is a rational number, representing the outcome of the operations performed. Such evaluations are common in algebra and highlight the importance of understanding how to manipulate exponents and perform operations with fractions accurately.