SOLUTION: A 4-digit car number has the following: 3rd digit and 2nd digit are d same.. Doubling 1st gives u 4th digit. Doubling first 2 digits gives u next 2. Find the car no..? T

Question 761081: A 4-digit car number has the following:
3rd digit and 2nd digit are d same..
Doubling 1st gives u 4th digit.
Doubling first 2 digits gives u next 2.
Find the car no..?
True test to ur intelligence....try dis 
Found 2 solutions by ramkikk66, htmentor:
Answer by ramkikk66(644) (Show Source): You can put this solution on YOUR website!
Answer is
Brute force way of trying all possible combinations for the middle two digits and eliminating them logically.
:)
Answer by htmentor(1343) (Show Source): You can put this solution on YOUR website!
Let the 2nd and 3rd digit = t
Let f = the 1st digit
Then the last digit = 2f
So the number looks like: f t t 2f
Doubling the first two digits gives the last two. Treat each as a two digit number.
Then we can write this in equation form as
2(10f + t) = 10t + 2f
20f + 2t = 10t + 2f
18f = 8t
9f = 4t
t = (9/4)f
Now the number looks like: f (9/4)f (9/4)f 2f
For the digits to be integers from 0 to 9, f must equal 4. Any other value gives a non-integer digit or a digit > 9.
So the solution is 4 9 9 8

RELATED QUESTIONS
A 4-digit car number has the following: 3rd digit and 2nd digit are d same.. Doubling... (answered by virali)
Just calculate the 4 digit no......... 4th digit is tree times of 1st digit 2nd nd 3rd... (answered by KMST)
find the 5 digit number that has the following characteristics. -no 2 digits are the... (answered by prince_abubu)
For a particular two digit number, the value of the number is 9 more than when the digits (answered by josgarithmetic)
For a particular two digit number, the value of the number is 9 more than when the digits (answered by stanbon)
A 4 digit number.1st squire is the 4 th number .2and 3 rd are same .1+2 = twice of 3rd... (answered by CubeyThePenguin)
if the 1st,2nd and 3rd digits are all the same. together they form a 3-digit number that... (answered by ankor@dixie-net.com)
There is a number containing 5 digits none of which is a zero. The 2nd digit is 3 times... (answered by MathTherapy)
A number where the first two digits are the reverse of 3rd & 4th digits and the last... (answered by ankor@dixie-net.com)