1. A list of inferences follows a statement. Mark each True, Probably True, Insufficient Data, Probably False, or False.

Two hundred students in their early teens voluntarily attended a recent weekend student conference in a midwestern city. At this conference, the topics of race relations and means of achieving lasting world peace were discussed, because these were the problems the students selected as being most vital in today's world.

  1. As a group, the students who attended this conference showed a keener interest in broad social problems than do most other students in their early teens.
    Probably true. Inference A is probably true because (as is common knowledge) most people in their early teens do not show so much serious concern with broad social problems. It cannot be considered definitely true from the facts given because these facts do not tell how much concern other young teenagers may have. It is also possible that some of the students volunteered to attend mainly because they wanted a weekend outing.
  2. The majority of the students had not previously discussed the conference topics in their schools.
    Probably false. Inference B is probably false because the students' growing awareness of these topics probably stemmed at least in part from discussions with teachers and classmates.
  3. The students came from all sections of the country.
    Insufficient data. There is no evidence for inference C. Thus there are insufficient data for making a judgment on the matter.
  4. The students discussed mainly labor relations problems.
    False. Inference D is definitely false because it is given in the statement of facts that the topics of race relations and means of achieving world peace were the problems chosen for discussion.
  5. Some teenage students felt it worthwhile to discuss problems of race relations and ways of achieving world peace.
    True. Inference E necessarily follows from the given facts; it therefore is true.

2. If you think that the given assumption is taken for granted in the statement, mark the statement Assumption Made. If you think the assumption is not necessarily taken for granted in the statement, mark the statement Assumption Not Made.

Statement: We need to save time in getting there, so we'd better go by plane.

  1. Going by plane will take less time than going by some other means of transportation.
    Assumption made. It is assumed in the statement that the greater speed of a plane over the speeds of other means of transportation will enable the group to reach its destination in less time.
  2. There is plane service available to us for at least part of the distance to the destination.
    Assumption made. In order to save time by plane, it must be possible to go by plane.
  3. Travel by plane is more convenient than travel by train.
    Assumption not made. The statement has to do with saving time, and says nothing about convenience or about any other specific mode of travel.

3. For the purpose of this test, assume that everything in the short paragraph is true. The problem is to judge whether or not each of the proposed conclusions logically follows beyond a reasonable doubt from the information given in the paragraph. If you think that the proposed conclusion follows beyond a reasonable doubt (even though it may not follow absolutely and necessarily), mark the statement Conclusion Follows. If you think that the conclusion does not follow beyond a reasonable doubt from the facts given, mark the statement Conclusion Does Not Follow. Remember to judge each conclusion independently.

A study of vocabulary growth in children from eight months to six years old shows that the size of spoken vocabulary increases from zero words at age eight months to 2,562 words at age six years.

  1. None of the children in this study had learned to talk by the age of six months.
    Conclusion follows. The conclusion follows beyond a reasonable doubt since, according to the statement, the size of the spoken vocabulary at eight months was zero words.
  2. Vocabulary growth is slowest during the period when children are learning to walk.
    Conclusion does not follow. There is no information given that relates growth of vocabulary to walking.

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