Problem at the Bank - Solution

 

A bank customer had $100 in his account.

He then made 6 withdrawals, totaling $100.

He kept a record of these withdrawals, and the balance left in the account, as follows:

Withdrawals Balance left
$50 $50
$25 $25
$10 $15
$8 $7
$5 $2
$2 $0
$100 $99

So, why are the Totals not exactly right?

There is no reason whatever why the customer's original deposit of $100 should equal the total of the balances left after each withdrawal.

The total of withdrawals in the left-hand column may equal $100, but it is purely coincidence that the total of the right-hand column is close to $100.

Let us show another example, but starting with $200 in the bank:

Withdrawals Balance left
$50 $150
$25 $125
$10 $115
$8 $107
$5 $102
$2 $100
$100 $699

 

Moral of this story? Don't Total Balances.

 

Puzzle supplied by Richard Rider