There is a 4 digit card number,

4th digit is double of 1st digit,

2nd n 3rd digits are same,

And last digits together are double of first two digits

**Can you guess the car number?**

Check your answer:-

Click here to see Explanation

lets assume first digit is x, then the 4th digit will be 2x.

also assume 2nd and 3rd digits are y.

then from => last two digits are double of first two digits, we can say

also assume 2nd and 3rd digits are y.

then from => last two digits are double of first two digits, we can say

**y(2x) = 2*(xy)**We can rewrite is as 10y + 2x = 20x + 2 y 8y = 18x 4y = 9x; => y/x = 9/4 as x and y are integers y => 9, x => 4

thus the car number is **4998**