X= 2 y= 3
x=4 y= 3
The slope is 0 since y doesn't change.
Answer:
The probability of testing positive for one is 0.20.
The probability of testing negative for one sample is (1-0.2)=0.8.
We only save time when all five are negative, which has a probability of 0.8^5=0.32768.
This means that the expected number of tests is
combined sample tests negative = 1 with probability 0.32768
combined sample tests positive = 1+5 retests = 6 with probability 0.67232
Expected number of tests
=Σ nipi / n
=(1*0.32768+6*0.67232)/5 [divide by 5 because we tested 5 samples]
= 0.87232 < 1
So yes, there is a saving.
Note: In practice, all medical tests are not absolute, i.e. they give false-positives(α) and false-negatives (β). The ratios 1-α and 1-β are respectively measures of specificity and sensitivity.
These two parameters complicate the simplistic evaluation above.
Let b>a
We are told that b=a+6 and that a+b=30
Using the value of b=a+6 in a+b=30 gives you:
a+(a+6)=30 combining like terms on left side
2a+6=30 subtract 6 from both sides
2a=24 divide both sides by 2
a=12, and since b=a+6
b=18
So the two numbers are 12 and 18.
Answer:
14
Step-by-step explanation:
it's going up by 2 everytime so you just take away 2
