A) To establish a sampling plan, follow these 5 steps:
1) Identify the sample population: which customers will you reach out to?
Those who purchased a new car during a specific year.
2) Determine the population size: how many customers will you contact?
From the 30,000 car buyers, select 1,000 customers to contact.
3) Select contact method: what is your means of contacting customers?
Since you have a list with names and addresses, mailing questionnaires is feasible.
4) Define the sampling frame: what is the timeline or deadline for contacting customers?
Send out questionnaires and allow two months for responses.
5) Decide on the analysis approach: is your research qualitative or quantitative?
You aim for quantitative research, so you will use probabilistic sampling.
B) The 32.5% probability relates only to those customers who experienced mechanical issues, specifically power door lock problems, and does not account for those without any problems or those reporting issues after the first 5,000 miles.
C) To estimate the probability of power door lock problems among all customers within the first 5,000 miles, consider the entire sample:
P = 13 / 1000 = 0.013
Therefore,
N = 0.013 × 30,000 = 390
Thus, the estimated number of new cars that had power door lock issues within 5,000 miles is 390.
For the equation Z^5=-7776i, we deduce that Z=+6.
90kg of sand was divided into 3 bags, constituting a total of 2+3+7=12 sections.
90kg/12=7.5kg
The smaller bag comprises 2 sections, hence it weighs 7.5kg*2=15kg
The medium-sized bag consists of 3 sections, leading to a total weight of 7.5kg*3=22.5kg
The larger bag encompasses 7 sections, resulting in a weight of 7.5kg*7=52.5kg
Thus, the ratio 2:3:7 translates to 15kg:22.5kg:52.5kg
Verifying, 15kg+22.5kg+52.5kg equals 90kg
To tackle the problem, the general approach is to convert all measurements into the smallest unit possible.
a. 3 km 9 hm 9 dam 19 m + 7 km 7 dam
3,000 m 900 m 90 m 19 m + 7,000 m 70 m = 4,009 + 7,070 = 11,079 m
b. 5 sq.km 95 ha 8,994 sq.m + 11 sq. km. 11 ha 9,010 sq. m.
5,000,000 sq m 95,0000 sq m 8,994 sq m + 11,000,000 sq m 110,000 sq
9,010 sq m
5,103,994 sq m + 11,119,010 sq m = 16,223,004 sq m
c. 44 m - 5 dm
44 m - 0.5 m = 43.5 m
d. 73 km 47 hm 2 dam - 11 km 55 hm
73,000 m 4,700 m 20 m - 11,000 m 5,500 m
77,720 m - 16,500 m = 61,220 m
An equivalent decimal represents the same quantity as another decimal; here, the 0 does not contribute any value.