posted by Lee .
The manager of the aluminum recycling division of Environmental Services wants a survey which will tell him how many households in the city of Seattle, Washington, will voluntarily wash out, store, and then transport all of their aluminum cans to a central recycling center located in the downtown area and only open on Sunday mornings.
A random survey of 500 households determines that 20% of the households would do so and that each participating household expects to recycle about 100 cans monthly with a standard deviation of 30 cans. (a) What is the 95% confidence interval regarding the percentage of households expected to recycle? (b) What is the 95% confidence interval regarding the number of cans to be recycled?