Answer:
Step-by-step explanation:
This is a conditional probability exercise.
Let's name the events :
I : ''A person is infected''
NI : ''A person is not infected''
PT : ''The test is positive''
NT : ''The test is negative''
The conditional probability equation is :
Given two events A and B :
P(A/B) = P(A ∩ B) / P(B)
P(A/B) is the probability of the event A given that the event B happened
P(A ∩ B) is the probability of the event (A ∩ B)
(A ∩ B) is the event where A and B happened at the same time
In the exercise :
We are looking for P(I/PT) :
P(I/PT)=P(I∩ PT)/ P(PT)
P(PT/I)=P(PT∩ I)/P(I)
0.904=P(PT∩ I)/0.025
P(PT∩ I)=0.904 x 0.025
P(PT∩ I) = 0.0226
P(PT/NI)=0.041
P(PT/NI)=P(PT∩ NI)/P(NI)
0.041=P(PT∩ NI)/0.975
P(PT∩ NI) = 0.041 x 0.975
P(PT∩ NI) = 0.039975
P(PT) = P(PT∩ I)+P(PT∩ NI)
P(PT)= 0.0226 + 0.039975
P(PT) = 0.062575
P(I/PT) = P(PT∩I)/P(PT)
Answer:
4 for the first one, 1 for the second one
Step-by-step explanation:
Answer:
$1,045.21
Step-by-step explanation:
Answer:
The volume of the wood used is
Step-by-step explanation:
<u>The Volume of a Rectangular Cuboid</u>
In a rectangular cuboid, all angles are right, and the opposite faces are equal.
The volume of a cuboid of dimensions a,b,c is:
V=a.b.c
The rectangular box is made of wood with externals dimensions of 25 cm by 20 cm by 15 cm.
The external volume of the box is:
The walls of the box are 0.5 thick each, this means that the internal dimensions are 1 cm less than the external dimensions, including the lid.
Thus the internal volume is:
The volume of the wood used is the difference between the external and the internal volumes:
The volume of the wood used is