Jay's mean score for four quizzes is 99. ​ ​His scores for the first three quizzes are 88 , 55 , and 99. ​ ​What is Jay's score for the last quiz?

154

Step-by-step explanation:

The mean is calculated by adding up all the numbers and dividing by the number of observations added up.

The above can therefore be expressed as:

(88 + 55 + 99 + x) / 4 = 99

242 + x = 99 * 4

242 + x = 396

x = 396 - 242

x = 154

fa tha first one you gonna add y to both sides

it look like this

x-y+y=6+y

x=y+6

therefore your answer is

x =y+6

fa tha second one

you gonna flip tha equation

it gonna look like x-4y=y

then add 4 to both sides

it gonna look like tha

x-4 +4 =y +4

so therefore tha answer is x=y+4

step-by-step explanation:

idk

step-by-step explanation: