This is one of those statistical follow-up questions and had to look for the options. Since the department of quality assurance is assessing the durability of the chairs being produced, the population that they are testing for quality is ALL THE CHAIRS THEY PRODUCED. Hope this helps.
A -21. It has to be 20 characters
By proportionality, for any number

, if T is multiplied by

then the same goes for M.
a) M has been multiplied by

hence


b) T has been divided by

hence

We can solve this by elimination, in order to do this we need to multiply the bottom equation by three to cross out the X
(x+5y=38)3 3x+15y=114
-3x+4y=95
3x+15y=114
then add the two equations together and the X will cancel out
19y=209
----- -----
19 19
y=11
then plug that in into one of the equations
x+55=38
-55 -55
x= -17
your answer is (-17,11)