A four digit no equals the sum of twice of its reversed and half of it What is the sum

18

Such number is 8712.
sum of digits = 8+7+1+2= 18
CHECK
8712 = 2*2178 + 8712/2
12 years agoHelpfull: Yes(6) No(2)
can you plz explain the process
12 years agoHelpfull: Yes(5) No(1)
Let the number be (abcd)

Then, (abcd)=2*(dcba) +0.5*(abcd)
or, 0.5*(abcd)=2*(dcba)
or, (abcd)=4*(dcba)

Then, dcba
* 4
------
abcd
------

Now, 'd' needs to be an even number (because 4*a = even number only)
Next 'd' cannot be 0 or 1.
So,d=2
Next,a=8;

Then we have the following two equations ==>>
4*b+3=c+10*x (where x= carry over)
and, 4*c=b (No carry,because 4*d=a is already 4*2=8)

Solving we get, b=7 and c=1 ...

So, ANSWER = a+b+c+d =8+7+1+2=18
so, ANSWER=18
12 years agoHelpfull: Yes(4) No(4)
given that 1st digit is 4 times of last digit and 2nd digit is 7 times of third digit... so first number will be the multiple of 4 and 2nd digit is the multiple of 7..
by checking 3rd digit should be 0 or 1 and last digit is 1 or 2 as when multiplied by 4 or 7 we should not get any double number

2 minutes enough for solving rather than writing equations
11 years agoHelpfull: Yes(0) No(0)

A four digit no. equals the sum of twice of its reversed and half of it.What is the sum of digit of such a no..?