i am a 4 digit number my first number is the double of the last number and my middle two numbers are the same what number am i

Answer 1

You must give more informations.

4 digits number can be write in form :

n = 1000 a + 100 b + 10 c + d

In this case :

a = 2 d

b = c

So :

n = 1000 ( 2 d ) + 100 c + 10 c + d

n = 2000 d + 100 c + 10 c + d

n = 2001 d + 110 c

For example :

d = 2

c = 1

n = 2001 d + 110 c = 2001 * 2 + 110 * 1

= 4002 + 110 = 4112

d = 2

c = 2

n = 2001 d + 110 c = 2001 * 2 + 110 * 2

= 4002 + 220 = 4222

d = 2

c = 3

n = 2001 d + 110 c = 2001 * 2 + 110 * 3

= 4002 + 330 = 4332

d = 4

c = 2

n = 2001 d + 110 c = 2001 * 4 + 110 * 2

= 8004 + 220 = 8224

etc.