B.2 The average life of a certain type of small motor is 10 years with a standard deviation of 2 years. The manufacturer replaces free all motors that fail while under guarantee. If she is willing to replace only 3% of the motors that fail, how long a guarantee should be offered? Assume that the lifetime of a motor follows a normal distribution.

6.2 The Standard Normal Distribution Table: Z-score and Probability A company produces steel rods. The lengths of the steel rods are normally distributed with a mean of 164.7 cm and a standard deviation of 2.5 cm. Find the probability that the length of a randomly selected steel rod is greater than 167.7 cm. Probability -

The incubation time for a breed of chicks is normally distributed with a mean of 29 days and standard deviation of approximately 3 days. Look at the figure below and answer the following questions. If 1000 eggs are being incubated, how many chicks do we expect will hatch in the following time periods? (Note: In this problem, let us agree to think of a single day or a succession of days as a continuous interval of time. Assume all eggs eventually hatch.) (a) in 23 to 35 days __ chicks(b) in 26 to 32 days  __chicks

On average, a banana will last 6.1 days from the time it is purchased in the store to the time it is too rotten to eat. Is the mean time to spoil greater if the banana is hung from the ceiling? The data show results of an experiment with 12 bananas that are hung from the ceiling. Assume that that distribution of the population is normal. 5.5, 6.6, 5.1, 8.4, 7.1, 5.1, 4.8, 5.1, 8.1, 5.4, 7, 7.8 What can be concluded at the the a = 0.05 level of significance level of significance? a. For this study, we should use Select an answer b. The null and alternative hypotheses would be: Ho: ? Select an answer ✓ H₁: ? Select an answer ✓ 4 c. The test statistic?v= (please show your answer to 3 decimal places.) (Please show your answer to 4 decimal places.) d. The p-value =