$P = \dfrac{\text{number of favorable ways}}{\text{total number of ways}}$
Problem
A disease is known to affect 1 in 10,000 people. A screening test for the disease shows a positive result for 99% of the people with the disease. The test also shows positive for 2% of people who do not have the disease. Find the probability that somebody is healthy given that they have positive test result?
| A. 99.51% | C. 46.32% |
| B. 12.32% | D. 78.36% |
Problem
Assume that a single depth charge has a probability of 1/2 of sinking a submarine, 1/4 of damage and 1/4 of missing. Assume also that two damaging explosions sink the sub. What is the probability that 4 depth charges will sink the sub?
Problem
The local weather forecaster says “no rain” and his record is 2/3 accuracy of prediction. But the Federal Meteorological Service predicts rain and their record is 3/4. With no other data available, what is the chance of rain?
| A. 3/5 | C. 1/6 |
| B. 1/4 | D. 5/12 |
Problem
A spider eats three flies a day. Until he fills his quota, he has an even chance of catching any fly that attempts to pass. A fly is about to make the attempt. What are the chances of survival, given that five flies have already made the attempt today?
| A. 1/2 | C. 3/4 |
| B. 1/4 | D. 2/3 |
Situation
Four army recruits went to the supply room to get their military boots. Their shoe sizes were 7, 8, 9 & 10. The supply officer, after being informed of their sizes, prepared the four pairs of boots they need. If the boots are handed to each of the four recruits at random, what is the probability that...
| A. 1/16 | C. 1/12 |
| B. 1/24 | D. 0 |
| A. 1/16 | C. 1/12 |
| B. 1/24 | D. 0 |
| A. 3/8 | C. 1/16 |
| B. 23/24 | D. 5/12 |
Problem
An engineering company prepares an estimate for a job. The cost of preparing the estimate is Php10,000. The amount of profit over and above the Php10,000 is Php25,000 if their estimate is accepted. The probability that their estimate will be accepted 0.7 and the probability that their estimate will not be accepted is 0.3. What is the expected profit?
| A. Php12,500 | C. Php14,500 |
| B. Php13,500 | D. Php10,500 |
Situation
If a chord is selected at random on a fixed circle what is the probability that its length exceeds the radius of the circle?
| A. 0.5 | C. 0.866 |
| B. 0.667 | D. 0.75 |
| A. 0.5 | C. 0.866 |
| B. 0.667 | D. 0.75 |
| A. 0.5 | C. 0.866 |
| B. 0.667 | D. 0.75 |
