Algebra Word Problem
posted by pj .
Peanuts are selling for $2 per pound, and cashews are selling for $5 per pound. How much of each type of nut would be needed to create 20lb. of a mixture that would sell for $2.75 pre puund?
Use the variables, p and c, to setup a system of equations. Solve.
p=numver of pounds of peanuts
c=numver of pounds of cashews
Could someone HELP ME PLEASE I'm LOST!!!

One equation would obviousy be
p + c = 20
The other equation would be based upon the total cost. 20 lb at 2.75/per lb should cost $55.
The same amount of money must equal the costs of the two ingredients, added together.
2 p + 5 c = 55.
Solve those two equations for the answer
Since 2p + 2c = 40,
3 c = 15
c = 5
p = 15 
A poll was taken of 100 students at a commuter campus to find out how they got to campus. The results were as follows: 31 said they drove alone, 39 rode in carpool, 35 rode public transportation, 10 used both carpool and public transportation, 7 used both a carpool and sometimes their own cars, 9 used buses as well as their own cars, 5 used all three methods. how many used none of the abovementioned means of transportation?