Zytel Corporation produces cleaning compounds and solutions for industrial and household use. While most of its products are processed independently, a few are related. Grit $337,$ a coarse cleaning powder with many industrial uses, costs $$2\mathrm{.}40$ a pound to make and sells for $$3\mathrm{.}60$ a pound. A small portion of the annual production of this product is retained for further processing in the Mixing Department, where it is combined with several other ingredients to form a paste, which is marketed as a silver polish selling for $$5\mathrm{.}60$ per jar. This further processing requires $1/4$ pound of Grit $337$ per jar. Costs of other ingredients, labor, and variable overhead associated with this further processing amount to $$2\mathrm{.}50$ per jar. Variable selling costs are $$0\mathrm{.}40$ per jar. If the decision were made to cease production of the silver polish, $$9,100$ of Mixing Department fixed costs could be avoided. Zytel has limited production capacity for Grit $337,$ but unlimited demand for the cleaning powder.

Required:

Calculate the minimum number of jars of silver polish that would have to be sold to justify further processing of Grit $337.$