Answer:
A=27 cm^2
B=24 cm^2
C=26 cm^2
D=28 cm^2
Step-by-step explanation:
Break each problem down into individual shapes.
For instance, A can be split into a 3 by 3 square and a 6 by 3 square.
Get the area by multiplying the length & height: A = L * H
For the triangles the area is the same equation divided by 2 A=LH/2
Shapes with unclear dimensions like C can be skipped and have their area revealed through process of elimination.
Answer:
35 percent
Step-by-step explanation:
To solve this problem we multiply the amount by the percent and add them up to get the total amount times the percent
amount * percent + amount * percent = total amount * percent
4 * .20 + 12 * .40 = (4+12) * x
.8 + 4.8 = 16 x
Combine like terms
5.6 = 16x
Divide by 16
5.6/16 = 16x/16
.35 =x
35 percent
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.