CM 2113 Chao Wang Exam Questions and
Correct Answers
Question 1
What the annual cost for a tractor is if a contractor is considering purchasing a used
tractor for $180,000 at 10% interest that she could use for 10 years and then sell for
an estimated salvage value of $10,000. Annual maintenance and repair costs for the
used tractor are estimated to be $15,000 per year.
Select one:
a. $43,710
b. $58,390
c. $41,970
d. $40,710
Correct Answer
a. $43,710
Question 1
The ________________ is very effective for side-casting material, particularly for
backfilling or making sidehill cuts.
Correct Answer
Angle Blade
Question 2
A contractor wants to investigate the production and cost differences of using a 4S
blade on a crawler-type dozer (D4H-4S). The material is dry clay and is to be moved a
distance of 150 ft from the beginning of the cut. The dozing is uphill on a 20% grade.
The operator will have average skill. The site conditions will be dark for visibility. The
material weighs 108 pcf in the bank state. Job efficiency is assumed to be equivalent
to a 50-min hour. What is the material-weight correction factor? Assume the percent
swell is 12%.
Correct Answer
.88
Page 1 of 79
,Question 3
What is the swing-depth factor for this machine based on the given scenario?
Correct Answer
1.00
Question 4
A 25-ton truck-mounted hydraulic crane is being used on a construction site. The
maximum horizontal distance from the center of rotation of the crane to the hoist line
of the crane when lifting a load of 9,000 lb will be 40 ft. Use Table 17.2 crane data to
select the minimum length boom required to safely hoist the load.
Correct Answer
64ft
Question 5
A contractor is planning to use single pusher scrapers to move 90,000 cubic yards of
soil, and the expected production of a single pusher scraper assuming adequate
pusher support is 230cy/hr. It has been decided there will be total 8 scrapers
operating on the site with a back-track loading method. The estimated cycle time for
each scraper is 7.5 min.
How many pushers are required to serve the fleet of 8 scrapers?
Correct Answer
2
Question 6
Which of the following is a job condition that could affect the operator's job
efficiency?
Correct Answer
Surface and weather conditions
Page 2 of 79
,Question 7
__________ is a technique whereby the blade end spillage from the first pass or the
sidewalls from previous cuts are used to hold the material in front of the dozer blade
on subsequent passes.
Correct Answer
Slot dozing
Question 8
Buckets of loaders are rated in both heaped and struck capacities. _________________ is
based on the SAE standard of a 2:1 material repose angle.
Correct Answer
Heaped capacity
Question 9
What is the actual production rate for this machine based on the given scenario?
Correct Answer
244 BCY/hr
Question 10
A contractor wants to investigate the production and cost differences of using a 4S
blade on a crawler-type dozer (D4H-4S). The material is dry clay and is to be moved a
distance of 150 ft from the beginning of the cut. The dozing is uphill on a 20% grade.
The operator will have average skill. The site conditions will be dark for visibility. The
material weighs 108 pcf in the bank state. Job efficiency is assumed to be equivalent
to a 50-min hour. What is the grade correction factor? Please choose a range from
the following where your reading will be within.
Correct Answer
.4-.6
Page 3 of 79
, Question 11
A contractor wants to investigate the production and cost differences of using a 4S
blade on a crawler-type dozer (D4H-4S). The material is dry clay and is to be moved a
distance of 150 ft from the beginning of the cut. The dozing is uphill on a 20% grade.
The operator will have average skill. The site conditions will be dark for visibility. The
material weighs 108 pcf in the bank state. Job efficiency is assumed to be equivalent
to a 50-min hour. What is the operator correction factor?
Correct Answer
.75
Question 12
A contractor has a project involving the construction of a small manufacturing plant.
The contractor has selected a borrow site and has decided to use 27-cubic yard dump
trucks to haul the needed fill material. The contractor has decided to use a hydraulic
excavator with a shovel attachment to load the trucks. The excavator has expected
productivity as 422cy/hr at 100% efficiency, and the truck cycle time excluding
loading is 0.48hr. The job site operation efficiency is assumed as 0.8.
How many dump trucks will be needed to work with the excavator?
Correct Answer
9
Question 13
What is the optimum depth of cut for this machine based on the given scenario?
Correct Answer
8.5ft
Question 14
A contractor wants to investigate the production and cost differences of using a 4S
blade on a crawler-type dozer (D4H-4S). The material is dry clay and is to be moved a
distance of 150 ft from the beginning of the cut. The dozing is uphill on a 20% grade.
The operator will have average skill. The site conditions will be dark for visibility. The
material weighs 108 pcf in the bank state. Job efficiency is assumed to be equivalent
to a 50-min hour. What is the work efficiency correction factor?
Correct Answer
.83
Page 4 of 79
Correct Answers
Question 1
What the annual cost for a tractor is if a contractor is considering purchasing a used
tractor for $180,000 at 10% interest that she could use for 10 years and then sell for
an estimated salvage value of $10,000. Annual maintenance and repair costs for the
used tractor are estimated to be $15,000 per year.
Select one:
a. $43,710
b. $58,390
c. $41,970
d. $40,710
Correct Answer
a. $43,710
Question 1
The ________________ is very effective for side-casting material, particularly for
backfilling or making sidehill cuts.
Correct Answer
Angle Blade
Question 2
A contractor wants to investigate the production and cost differences of using a 4S
blade on a crawler-type dozer (D4H-4S). The material is dry clay and is to be moved a
distance of 150 ft from the beginning of the cut. The dozing is uphill on a 20% grade.
The operator will have average skill. The site conditions will be dark for visibility. The
material weighs 108 pcf in the bank state. Job efficiency is assumed to be equivalent
to a 50-min hour. What is the material-weight correction factor? Assume the percent
swell is 12%.
Correct Answer
.88
Page 1 of 79
,Question 3
What is the swing-depth factor for this machine based on the given scenario?
Correct Answer
1.00
Question 4
A 25-ton truck-mounted hydraulic crane is being used on a construction site. The
maximum horizontal distance from the center of rotation of the crane to the hoist line
of the crane when lifting a load of 9,000 lb will be 40 ft. Use Table 17.2 crane data to
select the minimum length boom required to safely hoist the load.
Correct Answer
64ft
Question 5
A contractor is planning to use single pusher scrapers to move 90,000 cubic yards of
soil, and the expected production of a single pusher scraper assuming adequate
pusher support is 230cy/hr. It has been decided there will be total 8 scrapers
operating on the site with a back-track loading method. The estimated cycle time for
each scraper is 7.5 min.
How many pushers are required to serve the fleet of 8 scrapers?
Correct Answer
2
Question 6
Which of the following is a job condition that could affect the operator's job
efficiency?
Correct Answer
Surface and weather conditions
Page 2 of 79
,Question 7
__________ is a technique whereby the blade end spillage from the first pass or the
sidewalls from previous cuts are used to hold the material in front of the dozer blade
on subsequent passes.
Correct Answer
Slot dozing
Question 8
Buckets of loaders are rated in both heaped and struck capacities. _________________ is
based on the SAE standard of a 2:1 material repose angle.
Correct Answer
Heaped capacity
Question 9
What is the actual production rate for this machine based on the given scenario?
Correct Answer
244 BCY/hr
Question 10
A contractor wants to investigate the production and cost differences of using a 4S
blade on a crawler-type dozer (D4H-4S). The material is dry clay and is to be moved a
distance of 150 ft from the beginning of the cut. The dozing is uphill on a 20% grade.
The operator will have average skill. The site conditions will be dark for visibility. The
material weighs 108 pcf in the bank state. Job efficiency is assumed to be equivalent
to a 50-min hour. What is the grade correction factor? Please choose a range from
the following where your reading will be within.
Correct Answer
.4-.6
Page 3 of 79
, Question 11
A contractor wants to investigate the production and cost differences of using a 4S
blade on a crawler-type dozer (D4H-4S). The material is dry clay and is to be moved a
distance of 150 ft from the beginning of the cut. The dozing is uphill on a 20% grade.
The operator will have average skill. The site conditions will be dark for visibility. The
material weighs 108 pcf in the bank state. Job efficiency is assumed to be equivalent
to a 50-min hour. What is the operator correction factor?
Correct Answer
.75
Question 12
A contractor has a project involving the construction of a small manufacturing plant.
The contractor has selected a borrow site and has decided to use 27-cubic yard dump
trucks to haul the needed fill material. The contractor has decided to use a hydraulic
excavator with a shovel attachment to load the trucks. The excavator has expected
productivity as 422cy/hr at 100% efficiency, and the truck cycle time excluding
loading is 0.48hr. The job site operation efficiency is assumed as 0.8.
How many dump trucks will be needed to work with the excavator?
Correct Answer
9
Question 13
What is the optimum depth of cut for this machine based on the given scenario?
Correct Answer
8.5ft
Question 14
A contractor wants to investigate the production and cost differences of using a 4S
blade on a crawler-type dozer (D4H-4S). The material is dry clay and is to be moved a
distance of 150 ft from the beginning of the cut. The dozing is uphill on a 20% grade.
The operator will have average skill. The site conditions will be dark for visibility. The
material weighs 108 pcf in the bank state. Job efficiency is assumed to be equivalent
to a 50-min hour. What is the work efficiency correction factor?
Correct Answer
.83
Page 4 of 79
