If the average of the 3-digit numbers 335, 2x5, x35, 63x and 406 is 411, then what will be the average of x - 1, x - 3, x + 3 and x + 5?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 5
The average of the 3-digit numbers 335, 2x5, x35, 63x and 406 = 411
335 + 2x5 + x35 + 63x + 406 = 411 * 5 = 2055
2x5 + x35 + 63x = 2055 - 741 =1314
200 + 10x + 5 + 100x + 35 + 630 + x = 1314
111x = 1314 - 870 = 444
x = 444/111 = 4
Now,
The average of x - 1, x - 3, x + 3 and x + 5
= (3 + 1 + 7 + 9)/4 = 20/4 = 5