can not figure out this DS in Prep

[yangliu0401]

A certain one-day seminar consisted of a morning session and an afternoon seesion. If each of 128 people attending at least one of the sesions, how many of the people attended the morning seesion ONLY?

1. 3/4 of the people attended both sessions
2. 7/8 of the people attended the afternoon session.

OA is B. Why not C? How can stem 2 alone be sufficient?

[bhavikrao]

Yangliu,

The first choice says there 3/4 attended both the sessions, which means 96 attended both the sessions, 32 remains. This doesn't tell more info about those 32 folks

Second choice says 7/8th attended afternoon - that means 112 attended afternoon. So 128-112 attended Morning session

Hence B

thanks
Bhavik

[yangliu0401]

Yangliu,

The first choice says there 3/4 attended both the sessions, which means 96 attended both the sessions, 32 remains. This doesn't tell more info about those 32 folks

Second choice says 7/8th attended afternoon - that means 112 attended afternoon. So 128-112 attended Morning session

Hence B

thanks
Bhavik

Well, the Q asks the no. of people who attended the morning session ONLY. ,
From stem 2 we can just get there are 16 people who attended the morning session, but we can not get how many people attended both sessions.

[eracnos]

Definately those who did not come to the afternoon session are those who attend only morning ones since I they are suppose to be on @ least 1 of sessions.