**Answer:**

The conventional B/C ratio is 1.0868.

**Explanation:**

Here B / C ratio means the benefit by cost ratio, so here we will first individually calculate the benefit and cost which the parks and recreation department will receive.

BENEFIT RECEIVED =

$24,000(people that will come) x 2 (average hour ) x $.50 ( rate per hour )

= $24,000

calculating present value, where i = interest and n = number of years

$24,000 / (1+i)^1 + $24,000 / (1+i)^2 + _ __ _ + $24,000 / (1+i)^20

= $24,000 x [ 1 - 1 / (1+.03)^20 ] / .03 ( given i = 3% )

= $357,060

PRESENT VALUE OF COST INCURRED =

$150,000 + $12,000 / (1+i)^1 + $12,000 / (1+i)^2 + _ _ + $12,000 / (1+i)^20

= $150,000 + $12,000 x [ 1 - 1 / (1+.03)^20 ] / .03

= $328,530

B / C RATIO = $357,060 / $328,530

= 1.0868