The imperfect test gives positive results (indicating drug use) for 80% of all interns who actually use drugs but also (incorrectly) for 3% of those who do not use drugs. Suppose that only 10% of all of these interns actually use drugs. If an intern is tested negative, what is the probability that he/she uses drugs

The probability that an uses drugs given that the result was negative is 0.0224.

Step-by-step explanation:

Let's denote the events as follows:

D = an intern uses drugs.

X = the test result was positive.

The information provided is:

Compute the probability that the test result of an intern is positive as follows:

The probability that the test result of an intern is positive is P (X) = 0.107.

Compute the probability that the result is negative given that he/she uses drugs as follows:

Compute the probability that an uses drugs given that the result was negative as follows:

Thus, the probability that an uses drugs given that the result was negative is 0.0224.

solution:

we have to construct

∠m nt ≅ ∠p qr

the steps to draw this construction are

step 1: use a compass to draw an arc from point q which intersects the side pq at point a and the side qr at point b.

step 2: draw a segment nt and use the same width of the compass to draw an arc from point n which intersects the segment nt at a point x.

step 3:

step 4: join points n and y using a straightedge.

step 3:

option (d).maintaining the same width of the compass as ab, draw an arc from point x such that it intersects the arc drawn from n in a point y.

to draw   congruent angles , 1. width of compasses while drawing two angles should be same i.e from point at which angle has to be drawn, 2.the distance between the two points where the compass intersects the two sides should be same while drawing any two congruent angles.

let y equal to

the total fare and x is the mile of taxi ride. so the equation is

y = 0.55x + 1.75

since susie has

$10 to spend for a taxi cab, so he can have

10 = 0.55x +

1.75

x = 15 miles of

taxi ride

so the system of

inequality is

10 < 0.55x +

1.75

x > 2