An exam consists of 44 multiple-choice questions. each question has a choice of five answers, only one of which is correct. for each correct answer, a candidate gets 1 mark, and no penalty is applied for getting an incorrect answer. a particular candidate answers each question purely by guess-work.

using normal approximation to binomial distribution with continuity correction, what is the estimated probability this student obtains a score greater than or equal to 10?

0.3960

Step-by-step explanation:

X - no of questions answered correct is binomial since each question is independent of the other and there are two outcomes

p = Prob of any one question right = 0.2  (1/5)

n = 44

Normal approximation would be mean = np = 8.8 and Variance = npq = 7.04

Std dev =

X is N(8.8,2.6534)

Or Z =

Since we approximate discrete to continuous continuity correction is to be applied

means x≥9.5

P(X≥9.5) = 0.3960

step-by-step explanation:

12: 00 p.m. to 7: 00 p.m. is a total of 7 hours.

4: 00 p.m. to 7: 00 p.m. is a total of 3 hours.

this means that from 4: 00 p.m to 7: 00 p.m. this represents 3/7 of what was lost from 12: 00 p.m. to 7: 00 p.m.

after knowing this, after doing 11,600 - 6,800 = 4,800

4,800 represents 3/7 of what was lost for 7 hours.

we then divide 4,800 by 3 which gets 1,600.

because we know that 1,600 represents 1/7 of how much water was lost, we just have to multiply by 7, which gets 11,200.   after adding 11,200 to how much water was left at 7: 00 p.m. which was 6,800. 11,200 + 6,800 = 18,000

this means that the pool originally had 18,000 gallons in the pool.

you can also check your work by doing 18,000 - 4(1600), which becomes           1800 - 6400 which gets you 11,600.

0.6, 3/5, and 6% are the 3 same portion.

but, when they're all changed to a decimal they would equal to 0.6.

hope this , good luck!