Answer:
Therefore the company have to print either 47 or 12 t-shirt for its production cost to be $40 or less.
Step-by-step explanation:
Given that,
The function that models the production cost is
To find the number of t-shirt, we put f(t)=40 in given function.
∴40= 0.1t²-6t+100
⇒ 0.1t²-6t+100-40=0
⇒0.1 t²- 6t +60=0
⇒t²-60t+600=0
Applying quadratic formula , a=1, b= - 60 and c=600
= 47.32,12.67
≈47, 12
Therefore the company have to print either 47 or 12 t-shirt for its production cost to be $40 or less.