Write the equation using polar coordinates y^2=16x

Jack did 3/5 of all problems on his weekend homework before sunday. on sunday he solved 1/3 of what was left and the last 4 problems. how many problems were assigned for the weekend?

3. a sum of $2700 is to be given in the form of 63 prizes. if the prize is of either $100 or $25, find the number of prizes of each type.

John has 1/2 pound of oranges to share with julie. if they share the oranges equally, how much will each of them have?