## Logical Reasoning Set 9

Lavina wants to take 4 courses this semester. There are only 7 courses in which she is interested and that do not conflict with her job: three science courses - B, C and P - and four arts courses - L, D, M and H. To meet college requirements she must take two science courses this semester. There are some scheduling problems, however: L overlaps both C and M, which are subsequential; B is given at the same time as D. |

### Must Read:

### Check Your Learning:

**Q1)**If Lavina deceides to take L, what will her other three courses be?

**1)**B, P, and C

**2)**B, P, and H

**3)**B, P, and D

**4)**H, P, and C

**Q2)**If course P is at the same time as L and Lavina takes P, what further problem(s) will she face?

**1)**She won't be able to take two science classes

**2)**She won't be able to take B

**3)**She won't be able to take H

**4)**She won't be able to take 4 courses which interest her

**Q3)**If course C is changed to a time which Lavina cannot make and she deceides to take M, then which of the following would be her schedule?

**1)**B, P, L and M

**2)**B, P, D and M

**3)**B, P, H and M

**4)**H, P, L and M

**Q4)**If Lavina takes 4 courses this semester, she cannot?

**I)**Take D and not take C

**II)**Take M and not take C

**III)**Take L and not take P

**1)**I only

**2)**II only

**3)**III only

**4)**I and III only

**Q5)**Which of the following must always be true?

**I)**Lavina must take P if she takes M

**II)**Lavina must take C if she takes D

**III)**Lavina must take D if she takes C

**1)**I, II and III

**2)**II and III only

**3)**I and II only

**4)**II only

### Solutions and Explanations

**1)**If Lavina takes L then C and M are out. If C is out, then P and B is scheduled, then D is out. Hence, option 2.

**2)**When Lavina takes P, now scheduled at the same time as L, she cannot take L, C, or M because they overlap with the new P time. Only D or B may be taken, plus H. Hence, option 4.

**3)**If C is out then B, P are required. B precludes D and M displaces L. Hence, option 3.

**4)**III work by the same logic. In each case the taking of one of the non-science courses eliminates one of the science courses from consideration, thus requiring the other two science courses. II is trying to trap you into saying that since neither M nor C can combine with L, they must combine with each other. This is not true. It is possible to have a curriculum of M, P, B and H. Hence, option 4.

**5)**I must be true because if M is taken then C cnnot be taken, implies the remaining two science subjects must be taken. II must be true since D eliminates B, and requires the other two sciences. III need not be true since a curriculum of C, B, H and M is but one counter-example. Hence, option 3.