Solution Step 0/0
There is an interesting five-digit number A. With a 1 after it, it is three times as large as with a 1 before it. What is it?
A is between...
A is between...
Explanations
A with 1 after it is 10A + 1.A with 1 before it is 100,000 + A.
Then 10A + 1 = 3(100,000 + A), and A = 42,857.
[After Boris A. Kordemsky. The Moscow Puzzles: 359 mathematical recreations. 1972]
Check 20K and 30k
Check 30K and 40K
Check 40K and 50K
Check 50K and 60K
