The Precision Scientific Instrument Company manufactures thermometers that are supposed to give readings of o°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 O°C (denoted by negative numbers) and some give readings above O 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. Round to two decimal places. A. -1.48B.-1.89 C. -1.63 D. -1.75

It is given that the Precision Scientific Instrument company Manufactures thermometers that provide readings at 0 degree Celsius for the freezing point of water.

A quality control analyst examines the thermometers which provide readings in the bottom of 4%.

Using the standard normal table, we get

P(z < z) = 4%

P(z < z) = 0.04

See the probability of 0.04 in the standard normal corresponding to the z-value is = -1.75

Therefore,

P(z < -1.75) = 0.04

z = -1.75

So the temperature reading that separates the bottom of 4% from the other thermometers is - 1.75°C

Therefore correct option is (D). -1.75