
Beth B. answered 06/09/21
Math Tutor w/ over 2 years of teaching experience ready to help!
Hi, Jake!
So, for this particular type of question, what you need to do is start by finding the area of the larger space. The area of the rectangle is the larger space and contains the other 3 shape. Also, know that because we are trying to find the probability of something that we will be dealing with fractions/proportions/ratios here. What is the whole? What are the parts?
The whole is like I said - the large rectangle
The parts are: the triangle, the square, the circle and all of the additional unused space inside the rectangle.
So, what is the area of the rectangle? It is 22 inches x 14 inches
22 x 14 = (22 x 10) + (22 x 4) = 220 + 88 = 308 inches2
Now, we would normally find the areas of all of the other 3 shapes for a question like this, but since they have specified the square, that is all we need to be concerned with. What is the area of the square?
3 inches x 3 inches = 3 x 3 = 9 inches2
So the probability that if you closed your eyes and picked any random point inside the rectangle, that the point would be inside or on the square is
the area of the square ÷ the area of the rectangle = 9 ÷ 308 = about 3% probability. The answer should be D.
Does this make sense?