PSAT Math Multiple-Choice Practice Question 158
Question: 158
A major hospital conducted a study on a new experimental physical therapy method for some of its patients recovering from knee-replacement surgery. At the beginning of the study, 485 patients who had just had knee-replacement surgery were selected for the study; 194 of the patients were given the experimental physical therapy, and the remaining patients were put into conventional physical therapy. A summary of the recovery times for the patients who were in the study is shown in the table below.
Recovery Time for 485 Patients in the Study
Recovery Time | Experimental Therapy | Conventional Therapy |
6 months or less | 82 | 151 |
More than 6 months | 112 | 140 |
If a patient in the study is selected at random, which of the following is closest to the probability that the patient will have a recovery time of more than 6 months?
Correct Answer: C
Explanation:
C
The question asks for the probability a patient in the study selected at random will have a recovery time of more than 6 months. Probability is defined as . Read the table carefully to find the right numbers to set up the probability. Because the question states that a patient in the study is selected at random, the total # of possible outcomes is the total number of patients in the study, which is 485. Because the question asks for the probability that the patient will have a recovery time of more than 6 months, the # of outcomes that fit the requirement is the total number of patients with a recovery time of more than 6 months. Make sure to include both those in experimental physical therapy and those in conventional physical therapy to get a total of 112 + 140 = 252. Therefore, the probability is
. The question says is closest to, so select the closest choice. The correct answer is (C).
More Tests
- PSAT Math Multiple-Choice Test 1
- PSAT Math Multiple-Choice Test 2
- PSAT Math Multiple-Choice Test 3
- PSAT Math Multiple-Choice Test 4
- PSAT Math Multiple-Choice Test 5
- PSAT Math Multiple-Choice Test 6
- PSAT Math Multiple-Choice Test 7
- PSAT Math Multiple-Choice Test 8
- PSAT Math Multiple-Choice Test 9
- PSAT Math Multiple-Choice Test 10
- PSAT Math Multiple-Choice Test 11
- PSAT Math Multiple-Choice Test 12
- PSAT Math Multiple-Choice Test 13
- PSAT Math Multiple-Choice Test 14
- PSAT Math Multiple-Choice Test 15
- PSAT Math Multiple-Choice Test 16
- PSAT Math Multiple-Choice Test 17
- PSAT Math Multiple-Choice Test 18
- PSAT Math Multiple-Choice Test 19
- PSAT Math Multiple-Choice Test 20
- PSAT Math Multiple-Choice Test 21
- PSAT Math Multiple-Choice Test 22
- PSAT Math Multiple-Choice Test 23
- PSAT Math Multiple-Choice Test 24
- PSAT Math Multiple-Choice Test 25