Normal distribution...


I'm doing probability exercises and I found one that relates the normal distribution with sensitivity and specificity, and I do not know how to solve it.

It reads:

A continuous random variable in a healthy population is distributed according to N (12.1, 1.3). In a diseased population is distributed according to N (15.8, 1.5).

What is the value of the variable to be taken as the cutoff point for a sensitivity equal to 0.73?

What for a specificity of 0.93?

The only thing I can think of is to consider both the values of specificity and sensitivity as numbers Z and, apart from the formula of standardization, remove "x", which would be the respective cutoff points.

But I have no idea.

Could someone help me?

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