2-6=4/8 but I’m not really sure though
I can help here is a formula sheet
PhotosRemaining(x) = 745 pictures - (20 pictures/day)*(x), for x≥0
Answer:
The probability is 
Step-by-step explanation:
Let assume that the number of computer produced by factory C is k = 1
So From the question we are told that
The number produced by factory A is 4k = 4
The number produced by factory B is 7k = 7
The probability of defective computers from A is 
The probability of defective computers from B is 
The probability of defective computers from C is 
Now the probability of factory A producing a defective computer out of the 4 computers produced is

substituting values


The probability of factory B producing a defective computer out of the 7 computers produced is

substituting values


The probability of factory C producing a defective computer out of the 1 computer produced is

substituting values


So the probability that the a computer produced from the three factory will be defective is

substituting values


Now the probability that the defective computer is produced from factory A is


