grade 12 data management

Question

A PIN number for a bank card consists of 4-6 digits, with no restrictions. How many such PIN numbers are possible? (Repetition is allowed and 0 is allowed in first position)

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Avery and Bradley work at a large electronics manufacturer that produces DVD players. The defective rate on the assembly line has gone up to 12% and the manager wants to know the probability that a skid of 50 DVD players will contain at least 3 defective units.

a) Help Avery use the binomial distribution P(x)= nCx px qn-x to answer this question.

b)Help Bradley use the normal approximation to answer this question.

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A survey asked randomly chosen Star Wars fans how many times they watched any of the 6 movies in the series in the past six months. When the position of the percentile falls in a range, pick the midpoint of that range.

a) Find the median, first quartile, and third quartile for the data

Answer 1

For the first question,

We will start with the total number of 4 digit pins, then 5 digit pins, and 6 digit pins.

4 digit pins: 10 * 10 * 10 * 10 = 1000 (as each digit of the pin has no restrictions and can be 0 - 9)

5 digit pins: 10 * 10 * 10 * 10 * 10 = 10000 (as each digit of the pin has no restrictions and can be 0 - 9)

6 digit pins: 10 * 10 * 10 * 10 *10 * 10 = 10000 (as each digit of the pin has no restrictions and can be 0 - 9)

Due to how the digit pins can be 4, 5, or 6 digits in length we will add those combinations. 1000 + 10000 + 100000 = 111,000 different possible pin numbers based on no restriction pins of length 4, 5, or 6.