Question

I had a question on my stats homework that gave me a distribution table with a list of hours and a list of frequency’s and then it asked me to find the probibility that X < or = to 3.6. I tried using the calculator by using normalcdf but non of the answers were correct and i was wondering if you knew how to imput it in the calculator to give me the answer. The hours were like 0-2, 3-4, and so on and the frequency’s were like 888,1256 and so on. I imput the frequency’s in list 1 but i don’t know how to incorporeal that when trying to find the probability.

Answer 1

Solution

Back-up Theory

Probability = relative frequency i.e., frequency/total frequency

Now to work out the solution,

We want P(X ≤ 3.6)

= cumulative frequency up to 3.6/total frequency

Now frequency of [0 - 2] = 888.

Frequency of [3 - 4] = 1256

So, frequency from 3 to 3.6 = 1256 x 0.6 = 753.6

Thus. cumulative frequency up to 3.6 = 888 + 753.6 = 1641.6

And probability = 1641.6/Total frequency Answer

Just a point

You have done well to raise your query specifically. In such cases, after making the specific query, it may a good idea to give the full question. It normally would give the Subject Expert a total perspective of the question which in turn would yield a better a response from the Expert.

DONE