The mean of two numbers x and y is 4. Find the mean of four numbers x, 2x, y and 2y

  • A 2
  • B 4
  • C 6
  • D 8
waec 2022mathematics

The correct answer is C. 6

Since the mean of the two numbers x and y is:

\(\frac{x+y}{2}\) = 4

 x+y =2 * 4

x+y = 8

then we get:

\(\frac{x+2x+y+2y}{4}\)

=(\(\frac{3x+3y}{4}\))

= 3(\(\frac{x+y}{4}\)) → 3(\(\frac{8}{4}\)) 

= 3 * 2

= 6

Previous question Next question