Question

in order to improve evacuation routes out of new orleans in the event of another major disaster such as hurricane katrina, the louisiana department of transportation is planning to construct an additional bridge across the mississippi river. two alternatives are being considered: a suspension bridge and cantilever bridge. the department uses an interest rate of 8% and plans for 50-year life for either bridge. which design has the better pw? show your calculations in your working document.

Answer 1

The Louisiana Department of Transportation is comparing the present worth (PW) of a suspension bridge and a cantilever bridge for improving evacuation routes in New Orleans. The better design would have the higher present worth. Calculating the present worth of each design will determine the better option.

Step-by-step explanation:

The project is comparing the present worth (PW) of two bridge designs, a suspension bridge and a cantilever bridge. The Louisiana Department of Transportation plans to construct an additional bridge across the Mississippi River to improve evacuation routes in the event of a disaster like Hurricane Katrina. They are considering two alternatives with a 50-year life span and an 8% interest rate. To determine which design has the better PW, we need to calculate the present worth of each design and compare them.

To calculate the present worth, we can use the formula:

PW = C × (1 - (1 + i)^(-n)) / i

Where:

• PW is the present worth
• C is the cost or benefit per year
• i is the interest rate per year
• n is the number of years

We can use this formula to calculate the PW for both the suspension bridge and the cantilever bridge. The design with the higher PW would be considered the better option.