Question

If the average of the numbers 4,6,x and 2x is 10 what is the value of X?

Answer 1

10

Explanation:

the average is the sum of all the numbers divided by the amount of numbers. in this case the number to divide by is 4.

if x is equal to 10, then we would get this equation:

4+6+10+2(10)

10+10+20=40

40 divided by 4 equals 10.

Answer 2

x=10

Explanation:

• The average value of a finite serie of numbers "n" equals
  `(1)/(n) \sum_1^n{x_n}`, which is the same as
  `(1)/(n)* (x_1,x_2,....,x_n)`.
• You can apply this equation to your problem to start solving this problemmusing the serie of numbers you have: (4,6,x,2x).

• Following the previous equation, in this particular case n=4 (there are four values to calculate the average value), then the average can be calculated as follow:
  `(1)/(4)*{(4+6+x+2x)` and this equals
  `10=(1)/(4)*({10+3x})`
• ⇒
  `40=10+3x`. Substracting 10 from both sides, and dividing this result by 3, we get x=10.