3 packets of fries cost £4.20 How much does 5 packets of fries cost?
Select one
a. £6.40
b. £6.00
C. £7.00​

C

Step-by-step explanation:

First, divide £4.20 by 3 to get the price for 1 packet.

4.20/3 = 1.4

5 packets is 5 times that, so multiply 1.4 times 5. You get 7. So 5 packets costs £7.00

P(POSc/Sc)

Step-by-step explanation:

As,

POS= Test has positive results

and

S=Adult has tuberculosis.

The test correctly identifies 74.6% of the time adults with a tuberculosis and correctly identifies those without tuberculosis 76.53% of the time.

In the above statement 76.53% describes the probability of adult who don't have tuberculosis gets the negative results as test is correctly identifying.

So, getting negative results means that not positive results and for this event the notation of complement POSc is used. Also, not having tuberculosis can be denoted as Sc. So,

POSc= Test has negative results

Sc=Adult hasn't tuberculosis

Thus, P(POSc/Sc) depicts the probability of adults not having tuberculosis gets correct results.

Hence,  P(POSc/Sc)=76.53%