Answer:
22.5
Step-by-step explanation:
To find the rate of speed per hour, you need to divide the kilometer (90) by the hours (4).
90/4=
22.5
If 25% of the people <em>are</em> vaccinated, then 75% of the people are <em>not</em> vaccinated. Of those not vaccinated, each has a 50% chance of contracting the disease. The probability that someone is both not vaccinated and contracts the disease is (0.75)(0.5)=0.375.
The probability that someone is vaccinated and contracts the disease is (0.25)(0.1)=0.025 (it is multiplied by 0.1 because if the vaccine is 90% effective, then there is a 10% chance someone that is vaccinated can contract the disease.
Add these together for the total: 0.375+0.025=0.4
There is a 40% chance that someone chosen at random will contract the disease.
First, draw a diagram to visualize the situation:
As we can see, the difference between the x-coordinates of the points is the length of one leg of a right triangle, and the difference between the y-coordinates is the length of the other leg.
Then, for the given points (-5,4) and (8,-3), the distance given by the Pythagorean Theorem is:

Therefore, the distance between the points (-5,4) and (8,-3) is: √218.