Smith Engineering is in the process of reviewing the salaries of their surveyors. During this review, the company found that an experienced surveyor can survey a roadbed in 7 hours. An apprentice surveyor needs 9 hours to survey the same stretch of road. If the two work together, find how long it takes them to complete the job.

T = 3.5 hours

Step-by-step explanation:

this is a rate problem.

an experienced surveyor takes 7 hours to survey a roadbed

an apprentice surveyor takes 9 hours to survey a roadbed

the rate of the experienced surveyor =

the rate of the apprentice surveyor =

if the two work together ,

T =

T = 3.5 hours

x = central angle apc = measure of minor arc ac

the two angles x and 30 add to 180, so x+30 = 180 and x = 180-30 = 150. the measure of minor arc ac is 150 degrees.

what we need to do from here is find the circumference and then multiply it by x/360 since there are 360 degrees in a circle. in this case, x = 150, so x/360 = 150/360 = 15/36 = 5/12. the shortest distance along the curve from a to c is 5/12 of the distance around the entire circle (aka circumference)

c = circumference

c = pi*d

c = pi*24

c = 24pi

now multiply this by 5/12 to get

distance along minor arc ac = (5/12)*(circumference)

distance along minor arc ac = (5/12)*(24pi)

distance along minor arc ac = 10pi

the formula you can use is

l = (x/360)*pi*d

with

l = length of minor arc

x = central angle

d = diameter

which essentially is the steps we took though a bit differently.