A large but sparsely populated county has two small hospitals, one at the south end of the county and the other at the north end
. The south hospital’s emergency room has four beds, whereas the north hospital’s emergency room has only three beds. Let X denote the number of south beds occupied at a particular time on a given day, and let Y denote the number of north beds occupied at the same time on the same day. Suppose that these two rv’s are independent; that the pmf of X puts probability masses .1, .2, .3, .2, and .2 on the x values 0, 1, 2, 3, and 4, respectively; and that the pmf of Y distributes probabilities .1, .3, .4, and .2 on the y values 0, 1, 2, and 3, respectively.a. Display the joint pmf of X and Y in a joint probability table.b. Compute P(X # 1 and Y # 1) by adding probabilities from the joint pmf, and verify that this equals the product of P(X # 1) and P(Y # 1).c. Express the event that the total number of beds occupied at the two hospitals combined is at most 1 in terms of X and Y, and then calculate this probability.d. What is the probability that at least one of the two hospitals has no beds occupied?Devore, Jay L.. Probability and Statistics for Engineering and the Sciences (Page 210). Brooks Cole. Kindle Edition.
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Isosceles right triangles have two equal sides (a and b) that are not the hypotenuse (c). And when two sides are equal, so are their opposite angles. There are only 180° degrees in any triangles, thus the right angle = 90°, so 90 left for the two equal, means that 2x=90,
x = 45°.
There are several ways to go about solving a triangle like this. The best and easiest is simply to memorize that the hypotenuse is exactly root2 times the other sides. Or, each isosceles side is the hypotenuse (c) ÷ root2
Another way to do it is the longer proof of Pythagorean Theorem:
x = 45°.
There are several ways to go about solving a triangle like this. The best and easiest is simply to memorize that the hypotenuse is exactly root2 times the other sides. Or, each isosceles side is the hypotenuse (c) ÷ root2
Another way to do it is the longer proof of Pythagorean Theorem: