The Precision Scientific Instrument Company manufactures thermometers that are supposed to give readings of 0°C at the freezing point of water. Tests on a large sample of these thermometers reveal that at the freezing point of water, some give readings below 0°C
(denoted by negative numbers)and some give readings above 0°C (denoted by positive
Numbers). Assume that the mean reading is 0°C and the standard deviation of the readings is
1)00°C. Also assume that the frequency distribution of errors closely resembles the normal
Distribution. A thermometer is randomly selected and tested. A quality control analyst wants
To examine thermometers that give readings in the bottom 4%. Find the temperature reading
That separates the bottom 4% from the others.
A) −°1.75
B) −°1.63
C) −°1.48
D) −°1.89

Question

Quizplus · Accepted Answer

The z-score corresponding to the bottom 4% is -1.75. The temperature reading that separates the bottom 4% from the others is therefore 0°C - 1.75°C = -1.75°C.

The Precision Scientific Instrument Company Manufactures Thermometers That Are Supposed