MATH please help!
posted by kIM .
A manufacturer produces three types of radios: deluxe, standard and economy. Each radio uses three different types of transistors: P, Q and R. The deluxe radio uses 2 P's, 7 Q's and 1 R. The standard contains 2 P's, 3 Q's and 1 R, and the economy model requires 1 P, 2 Q's and 2 R's.
How many radios of each type can be constructed if the total number of transistors (P's, Q's and R's) available are 2200, 3400 and 1400 respectively and all transistors must be used?

Sorry about the confusion, which is not helped with at least 6 copies of identical questions, in addition to others that may have been deleted.
http://www.jiskha.com/display.cgi?id=1310358660
http://www.jiskha.com/display.cgi?id=1310104811
http://www.jiskha.com/display.cgi?id=1310104728
http://www.jiskha.com/display.cgi?id=1310355002
http://www.jiskha.com/display.cgi?id=1310104839
http://www.jiskha.com/display.cgi?id=1310413630
It would be much easier to respond to the original post, or make a new post with reference to the old post by number or by date and time.
Let
D=number of deluxe units
S=number of standard units
E=number of economy units
Set up equations for each type of transistor, forcing the total number used to the quantity available:
For type P:
2D+2S+E=2200
For type Q:
7D+3S+2E=3400
For type R:
D+S+2E=1400
Solving the above three simultaneous equations will give the quantities required. I get a total of 1200 units.