Answer:
About 2 of their next 5 deserts sold would be brownies.
Let's represent this by fractions. If 8 out of the 20 desserts they sold were brownies, that would make the fraction 8/20 represent how many brownies were sold.
Now if you reduce this fraction, you get 2/5, which tells about how many brownies will be sold in the next 5 brownies judging by the other data.
A door alarm works in 72 out of 100 cases.
surveillance camera works in 68 out of 100 cases.
The probability that method A is used = 72/100
The probability that method B is used = 68/100
Since both method are used we find the probability of A and B
Probability ( A and B) =
* 
=
To find the area of the triangle you would have to plug in the numbers for this equation: A= Hxb/2
So in your case 14x10/2
140/2= 70 and that would be your answer. Answer:G