Astudent takes 60 voltages readings across a resistor and finds a mean voltage of 2.501v with a sample standard deviation of 0.113v. assuming that errors are due to random processes, how many of the readings are expected to be greater than 2.70v?

There are 2 expected readings greater than 2.70 V

Solution:

As per the question:

Total no. of readings, n = 60 V

Mean of the voltage,

standard deviation,

Now, to find the no. of readings greater than 2.70 V, we find:

The probability of the readings less than 2.70 V, :

Now, from the Probability table of standard normal distribution:

Now,

Now, for the expected no. of readings greater than 2.70 V:

No. of readings expected to be greater than 2.70 V =

No. of readings expected to be greater than 2.70 V = ≈ 2