How much is 20 shilingi ishirini worth?

"20 shilingi ishirini" translates to "20 shillings twenty" in English, which suggests it's referring to a total of 40 shillings. If you are asking for its worth in a specific currency, please specify which currency you want it converted to, as the value of shillings can vary depending on the country (e.g., Kenyan shilling, Tanzanian shilling, etc.).