Karla scored 75, 80, and 92 on her history quizzes. What is the minimum score she needs on her next quiz to have a mean of 85?

The answer should be 93.

Step-by-step explanation:

So this took a lot of work to figure out, I did not solve it normally.

What i first did was add 75, 80, and 92 to get = 247. 247/3 was only 82, but in the equation you said the score on her next quiz, which means I would need to divide by 4.

But that was not possible with the numbers I had.

i started adding numbers to see if I would get the mean of 85, and eventually I added 93. to get 340, which I divided by 4 (the number of quizzes that were taken) to get the mean of 85.

so yeah, I made it more complicated than it need to be, but that's the answer lol

-your very overworked friend who went to great extent to solve this problem,

Azalea

since your problem is x^4 = 81, what you have to undeo is the "to the fourth power" part.

the inverse (opposite operation) of "to the fourth power" is "to the fourth root".

  (x^4) ^ ¼   = 81 ^ ¼  

  81 = 3^4     so (3 ^ 4) ^ ¼   =   3 ^ 1   = 3

by hand: (3 ^ 4) ^ ¼   =   3 ^ (4 x ¼) = 3 ^ 1   = 3   (when you take a power to a power, multiply the exponents.)

or, do it by calculator. one way of finding the fourth root is to use ^ (1/4)

step-by-step explanation:

yes

step-by-step explanation: