Answer:
Step-by-step explanation:
Given that a multiple choice test 30 questions, and each question has 5 answer choices (exactly one of which is correct).
When a student taking the test guesses randomly on all questions,p for success in each trial = 1/5 =0.2
As there are two outcomes and each event is independent of the other
X no of correct questions is binomial with n = 30 and p = 0.2
If approximated to normal
mean=np = 15 and Variance = np(1-p) = 4.8
Std dev = 2.191
X is normal (15, 2.191)
His expected value = mean = np
Required prob = P(X>15) = P(X>14.5) using continuity correction
=P(Z>-0.5/2.191) = P(Z>-0.23) =0.5910
x < 22.5; Samuel has less than 22.5 minutes to finish the race in the estimated time.
<h3>What amount of time Samuel left for the race?</h3>
The given inequality is-
From here, we define the variable x.
x = Number of the minutes left for the race
From here we can find the value of x
We have then:
Hence, Samuel has less than 22.5 minutes to finish the race in the estimated time.
To know more about inequality follow
brainly.com/question/24372553
5678 divided by 45.7 is 124.245...
