4.3-4.9 Test

Craig is an accident reconstructionist. He arrives at an accident where there are 4 skid marks of different lengths. He finds their measures to be 85 ft, 92 ft, 88 ft, and 90 ft. It is an asphalt road with a drag factor of 0.9. Because he does not know the efficiency of the driver’s brakes, he assumes a brake efficiency of 75%. What is the minimum speed the driver could have been going? Round to the nearest mi/h.

The Jacksons are taking a trip to Florida. Mr. Jackson knows that it is about 1,050 miles to their destination in Florida from their home in Ohio. He knows the average speed along his route will be 75 miles per hour. How long is the drive? (Round to the nearest hour)

Nina’s car exponentially depreciates at a rate of 8% per year. If Nina bought the car when it was 5 years old for $14,000, what was the original price of the car? Round to the nearest hundred dollars.

Jared purchased a car for $31,200 five years ago. It depreciated at 5.9% per year. What is its worth now? Round to the nearest hundred dollars.

Melissa was traveling at 45 mi/h on a concrete road with a drag factor of .78. Her brakes were working at 95% efficiency. To the nearest tenth of a foot, what would you expect the average length of the skid marks to be if she applied her brakes in order to come to an immediate stop? Round to the nearest tenth.

The ratio of boys to girls in a math classroom is 6:5. There are 55 students in the classroom. How many boys are present?

After how many years will the value of the car and what you have paid on the vehicle be equal? Round to the nearest tenth of a year.

The ratio of boys to girls in a math classroom is 6:5. There are 55 students in the classroom. What is the probability of choosing a girl? Round to the nearest tenth.

Jerome just purchased a 4-year-old car for $19,000. He was told that this make and model depreciates exponentially at 6.1% per year. What was the original price to the nearest hundred dollars?

You're traveling 41 mi/h when you see two young children crossing the street. What is your reaction distance?

What is the approximate braking distance for a car traveling 61 mi/h? Round to the nearest tenth.

Dustin is driving 53 mi/h on his way to work. He sees a dog 180 feet away. What will be his total stopping distance? Round to the nearest tenth.

An accident reconstructionist took measurements from yaw marks left at a scene. Using a 42-foot length chord, she determined that the middle ordinate measured approximately 6 feet. The drag factor for the road surface was determined to be 0.8. Determine the minimum speed that the car was going when the skid occurred to the nearest tenth.