Statistics

A maker of microwave ovens advertises that no more than 10% of its microwaves need repair during the first 5 years of use. In a random sample of 57 microwaves that are 5 years old, 13% needed repairs. At á=0.01, can you reject the maker’s claim that no more than 10% of its microwaves need repair during the first five years of use?

  1. 👍
  2. 👎
  3. 👁
  1. Null hypothesis:
    Ho: p < or = .10 -->meaning: population proportion is less than or equal to .10
    Alternative hypothesis:
    Ha: p > .10 -->meaning: population proportion is greater than .10

    Using a formula for a binomial proportion one-sample z-test with your data included, we have:
    z = .13 - .10 / √[(.10)(.90)/57] -->note: .90 represents 1 - .10

    Finish the calculation.

    Use a z-table to find the critical or cutoff value at 0.01 for a one-tailed test (upper tail). The test is one-tailed because the alternative hypothesis is showing a specific direction (greater than).

    If the z-test statistic calculated above exceeds the critical value from the z-table, reject the null. If the z-test statistic does not exceed the critical value from the z-table, do not reject the null.

    I hope this will help get you started.

    1. 👍
    2. 👎

Respond to this Question

First Name

Your Response

Similar Questions

  1. Science

    Determine the frequency of a microwave 6.0 cm in length.( A microwave is an electromagnetic wave.It travels through space at a speed of 3.0 x 10 ^8 m/s)

  2. Math!

    The table below shows the percentage of households that own a microwave in different countries. Construct a stem-and-leaf plot of the data. Country Percent Of Household With Microwave Ovens

  3. physics

    (a) Two microwave frequencies are authorized for use in microwave ovens: 900 and 2560 MHz. Calculate the wavelength of each. 1 cm (frequency = 900 MHz) 2 cm (frequency = 2560 MHz) (b) Which frequency would produce smaller hot

  4. Chemistry

    Microwave ovens emit microwave energy with a wavelength of 12.5 cm. What is the energy of exactly one photon of this microwave radiation?

  1. physics

    A microwave draws 5.0 A when it is connected to a 120 V outlet. If electrical energy costs $0.090 per kW·h, what is the cost of running the microwave for exactly 6 h?

  2. Statistics

    Automobile repair costs continue to rise with the average cost now at $367 per repair (U.S. News & World Report website, January 5, 2015). Assume that the cost for an automobile repair is normally distributed with a standard

  3. PHYSICS

    The microwaves in a microwave oven are produced in a special tube called a magnetron. The electrons orbit in a magnetic field of 9.3×10−2 T at a frequency of 2.6 GHz, and as they do so they emit 2.6 GHz electromagnetic waves.

  4. Physics

    Microwaves travel at the speed of light, 3.00× 108 m/s. When the frequency of microwaves is 3.67× 109 Hz, what is their wavelength? Answer in units of m

  1. Chemistry

    Microwave ovens emit microwave energy with a wavelength of 13.0 cm. What is the energy of exactly one photon of this microwave radiation?

  2. physics

    Microwave ovens typically cook food using microwaves the a frequency of about 3.00 GHz (gigahertz 10 to the nine Hz). Show the wavelength of these microwaves traveling at the speed of light is 10cm.

  3. chemistry 121

    Microwave ovens use microwave radiation to heat food. The microwaves are absorbed by moisture in the food, which is transferred to other components of the food. As the water becomes hotter, so does the food. Suppose that the

  4. Math -___-

    The table below shows the percentage of households that own a microwave in different countries. Constuct a stem-and-leaf plot of the data. Use the ‘|’ key (Shift + \ on most keyboards, just beside the backspace key) to create

You can view more similar questions or ask a new question.