Donna is saving money to buy a game. The game costs $30, and so far she has saved three-fifths of this cost. How much money has Donna saved?

Kelly is a salesperson at a shoe store, where she must sell a pre-set number of pairs of shoes each month. at the end of each work day the number of pairs of shoes that she has left to sell that month is given by the equation s=300-15x , where s is the number of pair of shoes kelly still needs to sell and x is the number of days she has worked that month. what is the meaning of the number 300 in this equation

The square pyramid has a volume of 441 cubic inches. what is the value of x? 1/7x is the height x is the base

In the diagram, ab is tangent to c, ab = 4 inches, and ad = 2 inches. find the radius of the circle.