Need algebra help 10 points to someone who gives correct asnswer?

Question

how do you solve for x?

3.8 - 4.2 - 5.3 - x - and the average is 4.8

i dont just want the aswer how do you get it?

Answer 1

If I understand your question, you are asking for what is x when you know that the average of 3.8, 4.2, 5.3 and x is 4.8?

Then you would just say that x+3.8+4.2+5.3=4.8

x+13.3=4.8

x=4.8-13.3

x=-8.5

Answer 2

ok well the average is all 4 numbers added together and divided by four, right?

so 3.8 + 4.2 + 5.3 + x = 19.2   (this is 4.8 times four)

then minus 3.8 and 4.2 and 5.3 from the right hand side and you'll get x

got it?

Answer 3

To find the average, you would first add 3.8, 4.2, 5.3, and x.  Then you would divide by the number of numbers you have, which is 4.  Since the average is given to you, set all of that equal to 4.8.  So, the process goes like this:

(3.8 + 4.2 + 5.3 + x) / 4 = 4.8

(13.3 + x) / 4 = 4.8

13.3 + x = 19.2  <----- multiplied both sides of the equation by 4

x = 5.9  <----- subtracted 13.3 from both sides

And the answer is 5.9.  if you wanna make sure its right, just find the average of all 4 numbers, except replacing the x with 5.9.  So

(3.8 + 4.2 + 5.3 + 5.9) / 4 = 4.8

(19.2) / 4 = 4.8

4.8 = 4.8  <----- answer is correct =]

Answer 4

what to you mean by - ?

cheers,

Answer 5

you now that to find the average of four numbers, you add them all together and divide by four. Therefore,

3.8  +  -4.2  +  -5.3  +  -x

-------------------------------------    = 4.8

                  4

Play around with that and you get

-5.7 + -x

-------------  = 4.8

      4

multiply by four to get rid of the denominator

-5.7 + -x  =  19.2

-x  =  24.9

x  =  -24.9

There you go.