Question

of 4 numbers the 4th is twice the 3rd, the 3rd is twice the 2nd, and the 2nd is twice the 1st, what is the 1st number, if the average of 4 numvers is 90​

Answer 1

Answer:

6

Step-by-step explanation:

Let x be the first number.

Then 2x, 4x, 8x are 2nd,3rd,4th numbers respectively.

So average = 90

= (x+2x+4x+8x)/4

90×4=15x

$x= \frac{360}{15} \\ x = 24$