Question

What is the correct answer? Plz explain.

Answer 1

Given:

cA(n)=5n+50

cC(n)=4n+80

and cC(n)<cA(n)

so

4n+80 < 5n + 50

Subtract 4n from both sides

4n-4n + 80 < 5n-4n +50

80 < n + 50

Subtract 50 from both sides,

30 < n