Question

The function for the cost of materials to make a shirt is f(x) = 5/6x + 5, where x is the number of shirts. The function for the selling price of those shirts is g(f(x)), where g(x) = 5x + 6. Find the selling price of 18 shirts.

106
120
185
196

Answer 1

x=6
g(f(x))=g(f(18))
=g(5/6*18 +5)
=g(20)
=(5*20)+6
=106

Answer 2

The selling price of 18 shirts is given by g(f(18))

g(f(x))= 5.f(x) + 6= 5[(5/6)x+5]+6=(25/6)x+25+6
g(f(x))=25/6)x+25+6
g(f(18))=25/6).18+25+6=106
the answer is 106. Enjoy the rest of your day :)