An electrical appliance uses four 15v batteries They are con

An electrical appliance uses four 1.5v batteries. They are connected in series so that the total voltage is the sum of the voltages in the four batteries. The population of batteries has a mean voltage of 1.5v with a standard deviation of 0.2v.

1.What is E(Total Voltage)?

2.What is Var(Total Voltage)?

3. Five randomly-selected resistors labeled 100-ohm are connected in series so that the resistance is additive. In reality, the resistors come from a population that is ~ N(100, 2.89). What is the probability that the resistance in the circuit is more than 11 ohm away from its expected value?

Solution