At fast-food restaurants, the lids for drink cups are made with a small amount of flexibility, so they can be stretched across the
mouth of the cup and then snugly secured. When lids are too small or too large, customers can get frustrated, especially if they
end up spilling their drinks. At one restaurant, large drink cups require lids with a diameter of between 3.95 and 4.05 inches.
The restaurant's lid supplier claims that the diameter of the large lids follows a normal distribution with mean 3.98 inches and
standard deviation 0.02 inch. Assume that the supplier's claim is true. The supplier is considering two changes to reduce the
percent of its large-cup lids that are too small to 1%: (1) adjusting the mean diameter of its lids, or (2) altering the production
process to decrease the standard deviation of the lid diameters.
(a) If the standard deviation remains at = 0.02 inch, at what value should the supplier set the mean diameter of its large-cup
lids so that only 1% are too small to fit?
Mean=
inches
(Round to 4 decimal places.)
(b) What effect will the change in part (a) have on the percent of lids that are too large?
By increasing the mean from 3.98 inches to the value I entered in part (a), the percentage of lids that are too large will
increase
Atten