he wait time (after a scheduled arrival time) in minutes for a train to arrive is Uniformly distributed over the interval [0,15]. You observe the wait time for the next 95 trains to arrive. Assume wait times are independent. Part a) What is the approximate probability (to 2 decimal places) that the sum of the 95 wait times you observed is between 670 and 796

81.74% probability that the sum of the 95 wait times you observed is between 670 and 796

Step-by-step explanation:

To solve this question, the uniform probability distribution and the normal probability distribution must be understood.

Uniform distribution:

A distribution is called uniform if each outcome has the same probability of happening.

The distribution has two bounds, a and b.

Its mean is given by:

Its standard deviation is given by:

Normal distribution:

Problems of normal distributions can be solved using the z-score formula.

In a set with mean and standard deviation , the z-score of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

n instances of the uniform distribution can be approximated to the normal with ,

Uniformly distributed over the interval [0,15].

This means that:

95 trains

, so:

What is the approximate probability (to 2 decimal places) that the sum of the 95 wait times you observed is between 670 and 796?

This is the pvalue of Z when X = 796 subtracted by the pvalue of Z when X = 670. So

X = 796

has a pvalue of 0.9761

X = 670

has a pvalue of 0.1587

0.9761 - 0.1587 = 0.8174

81.74% probability that the sum of the 95 wait times you observed is between 670 and 796

solution:

we have to construct

∠m nt ≅ ∠p qr

the steps to draw this construction are

step 1: use a compass to draw an arc from point q which intersects the side pq at point a and the side qr at point b.

step 2: draw a segment nt and use the same width of the compass to draw an arc from point n which intersects the segment nt at a point x.

step 3:

step 4: join points n and y using a straightedge.

step 3:

option (d).maintaining the same width of the compass as ab, draw an arc from point x such that it intersects the arc drawn from n in a point y.

to draw   congruent angles , 1. width of compasses while drawing two angles should be same i.e from point at which angle has to be drawn, 2.the distance between the two points where the compass intersects the two sides should be same while drawing any two congruent angles.