Mike is in charge of producing a sophisticated electronic device
and the deadline is coming up. The specifications for the device are stringent. In particular, the device
requires 60 capacitors which must operate within ±0.50 pF from a specified standard of 28 pFs.
The problem is that the supplier can provide capacitors that operate according to a normal dis-
tribution, with a mean of 28 pFs and a standard deviation of 1 pF (the capacitor characteristics are
independent random variables). Therefore, to have 60 capacitors that Mike can use in the electronic
device, he will have to order more than 60 from the supplier. These items are expensive, and Mike wants
to order the smallest batch that will have at least a 95% chance of containing enough usable capacitors.
Mike needs your help in figuring out the size of the order he should place.
(6.1) Easy. What is the probability that a capacitor provided by the supplier will meet the specifi-
cation needed for the electronic device?
(6.2) Challenging. What is the size of the order that Mike should place?