Question

Assume that thermometer readings are normally distributed with a mean of 0 degrees°C and a standard deviation of 1.00 degrees°C.

A thermometer is randomly selected and tested. The probability of getting a reading between 0.25 and 1.25 is?

Answer 1

Solution :

Given that,

mean = = 338

standard deviation = = 1.00

P (0.25 < x < 1.25 )

P ( 0.25 - 1.00 / 0 ) < ( x -  / ) < (1.25 - 1.00 / 0)

P (0.25 / 0 < z < 1.25 / 0 )

P (0.25 < z < 1.25)

P ( z < 1.25 ) - P ( z < 0.25 )

Using z table

= 0.8944 - 0.5987

= 0.2957

Probability = 0.2957