The average of the first and the second of three numbers is 15 more than the average of the second and the third of these numbers .what is the difference between the first and the third of these three numbers?

Correct Answer: None of these
Let Ist no = x 2nd no = y 3rd no = z According to Q. (x + y)/2 = 15 + (y + z)/2 Multiply above equation by 2 x + y = 30 + y + z So, x - z = 30 Difference of Ist & 3rd no is 30.