Take Any Three-Digit Integer, Reverse Its Digits, and Subtract

question 148

Short Answer

Take any three-digit integer, reverse its digits, and subtract. For example, 742 − 247 = 495. The difference is divisible by 9. Prove that this must happen for all three-digit numbers abc.

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Definitions:

Option Quoted

The listed price of an option contract on an exchange, often comprising its intrinsic value and time value.

Time Value

The additional amount an investor is willing to pay for an option or other financial product based on its potential to increase in value over time.

November 45 Call

A type of option contract that gives the holder the right, but not the obligation, to buy a stock or another financial instrument at a specified price (in this case, $45) on or before November's expiration date.

Risk-Free Rate Of Return

The assumed rate of return on an investment that carries no risk, typically illustrated by the return on government securities.