Acme Foods wants to make its chips saltier,but it doesn't want to spend more than it has to on salt.A sample of consumers are asked to compare its current chip (saltiness = 100)with saltier versions and to say whether the new version is saltier.On average,sample consumers reliably say the new chip is saltier when its saltiness value is 108,but not when its saltiness value is below 108.Assuming Acme Foods' sample consumers are representative of people in general,which of the following best represents the just noticeable difference for saltiness?
A)8%
B)108
C)80%
D)100

Question

Quizplus · Accepted Answer

The just noticeable difference (JND) is the minimum amount of change in a stimulus that can be detected by a person. In this case, the JND for saltiness is the smallest increase in saltiness value that consumers reliably perceive as saltier. From the given information, the JND for saltiness is 8 because consumers perceive the new chip as saltier when its saltiness value is increased by 8 (from 100 to 108) but not when it is increased by any smaller amount. Therefore, the correct answer is A) 8%.

Acme Foods Wants to Make Its Chips Saltier,but It Doesn't