A shop sells golf balls, golf clubs and golf hats. Golf balls can be purchased at a rate of \(25\) pennies for two balls. Golf hats cost \(£1\) each. Golf clubs cost \(£10\) each. At this shop, Ross purchased \(100\) items for a total cost of exactly \(£100\) (Ross purchased at least one of each type of item). How many golf hats did Ross purchase?