Question

Three manufacturers of plastic products a,b and c received an order to make 1950 plastic filters in the ratio 7:8:11.

Answer 1

7+8+11=26

So the first manufacturer  makes  7/26 of all filters
      the socond one makes    8/26 of all filters
and the third one makes  11/26 of all filters

A)
Number of plastic filters A:
                                               $A=\frac7{26}\cdot1950=7\cdot75=525$
Number of plastic filters C:
                                               $C=\frac{11}{26}\cdot1950=11\cdot75=825$

B)
Number of plastic filters B:
                                                       $B=\frac8{26}\cdot1950=8\cdot75=600$
85cents = 0,85$ (or €?)
Amount of money B will receive:
                                                         $600\cdot0,85=6\cdot85=510$
C)
The main thing that will change is the number of plastic filters to make:

1950-338=1612
So:
     Number of plastic filters A:
                                                    $A=\frac7{26}\cdot1612=7\cdot62=434$
     Number of plastic filters B:
                                                    $B=\frac8{26}\cdot1612=8\cdot62=496$
     Number of plastic filters C:
                                                    $C=\frac{11}{26}\cdot1612=11\cdot62= 682$