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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 remaining 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 colum may equal 100, but is 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