20
26p.
There were 21 Shillings in a Guinea.
There are ten shillings in half a pound.
There were 40 Shillings in the predecimal Two Pounds.
In the predecimal currency, there were 20 Shillings in One Pound. Therefore there would be 200,000 Shillings in £10,000 (predecimal).
Britain used Pounds, Shillings and Pence as their currency for many years. There were 12 Pence to the Shilling and 20 Shillings to the Pound. Many British Colonies and countries of the British Empire/Commonwealth also used Pounds, Shillings and Pence.
It depends on which currency you are using. In British coinage there were 20 shillings to the pound. Do the maths
a first class stamp = 26p
One US dollar is equal to 84.45 Kenyan shillings.
There were 20 Shillings in the British Pound every year, including 1910.
There were 20 Shillings in One Pound so, if you consider having 10,000 Pounds as being rich, is would take 200,000 Shillings to be rich.