Answer:
113.23 weeks
Step-by-step explanation:
First, let's calculate the total amount of tar in 10 packs of cigarettes. Each pack contains 20 cigarettes, so 10 packs would contain 10 x 20 = 200 cigarettes.
If each cigarette contains 5.00mg of tar, then the total amount of tar in 200 cigarettes would be 200 x 5.00mg = 1000mg.
To convert milligrams (mg) to pounds (lb), we need to know the conversion factor. Since 1lb = 453.592g, we can calculate that 1mg = 0.00000220462lb.
Therefore, 1000mg of tar is equal to 1000 x 0.00000220462lb = 0.00220462lb.
Now, let's calculate how many weeks it would take to inhale 0.25lb of tar.
If 0.00220462lb of tar is inhaled in 1 week, we can set up the following proportion:
0.00220462lb / 1 week = 0.25lb / x weeks.
Solving this proportion, we get:
0.00220462lb * x weeks = 0.25lb * 1 week.
Simplifying, we have:
x weeks = 0.25lb / 0.00220462lb.
x weeks = 113.23.
So, the person would have to smoke for approximately 113.23 weeks to inhale 0.25lb of tar.