Answer:
Step-by-step explanation:
First, convert 20 yds to 60 ft. and then from 60 ft to 720 in.
Use the formula for the nth term of an arithmetic sequence:
l = a + (n-1)d:
Here l = 720 ft, and a = 0. The common difference, d, is 16 in. Our task is to determine how many studs are needed.
Substituting the knowns, we get 720 = 0 + (n - 1)(16), which simplifies to:
720 = (n-1)(16).
Divide both sides by 16 to isolate (n-1): 45 = n - 1.
Adding 1 to both sides results in 46 = n.
46 studs total are needed; if the worker has already placed the first stud, then 45 additional studs are needed.