One Two Nine Part 1

Number Theory Level 2

I rearranged the digits of the number $A = 123456789$ to get $N$ . I noticed that when $N$ is written in reverse order, it is equal to $8A$ . What is $N$ ?

The answer is 213456789.

1 solution

Pi Han Goh
Sep 8, 2015

I think this is what the author is trying to say:

"If I rearrange the digits of the number 123456789, then I rewrite it in reverse order, the resultant number is 8 times the original number. What number did I rearrange to from the beginning?"

Solution:

Let $N$ denote the original number, which is 123456789. So $8N = 987654312$ . If I reverse the digits of $8N$ , I get $213456789$ which is the number desired.

Wrong, wrong, wrong. Here is the correct answer.

Python 3.4:

1	`print("Answer:", str((8 * 123456789))[::-1])`

Brock Brown - 5 years, 8 months ago

One Two Nine Part 1

The answer is 213456789.

1 solution

0 pending reports