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Logical reasoning

Logical thinking is the ability to make deductions that lead rationally to a certain conclusion. It is important to have good logic skills because they help you think things through and they also give you a good understanding of cause and effect relationships. In this test your logic IQ was assessed through your ability to comprehend and follow certain rules and conditions set forth in many of the questions. Generally speaking logic skills make divergent thinkers and have proven to be very successful in our daily lives. Furthermore when combined with social insight and and self awareness logic skills make us into effective human beings. Improving these skills will increase your IQ and give you a good base for academic and personal success.

26. Which number comes next in the following series?

4 5 8 17 44

  1. 60
  2. 80
  3. 95
  4. 125

125. The difference between the numbers follows this series: 1,3,9,27,81.

27. Which number comes next in the following series?

13 57 911 1315 1719

2123. All odd numbers beginning from one, in series. Alternatively, starting with 13, add 4 to each digit separately, and continue adding 4 to the result.

28. A company that packages household products follows the following guidelines in order to avoid dangerous product combinations.

Logic IQ question 28
  • Alcohol may be packed on Tuesdays, Thursdays and Fridays.
  • Baking soda can't be packed on Fridays.
  • Ammonia, can be packed only on Mondays and Wednesdays.
  • Bleach may be packed any day except for Friday.
  • Chlorine can't be packed on Wednesday.

On which days would it be possible for three products to be packaged together?

  1. All days.
  2. All days apart from Thursday.
  3. All days apart from Friday.
  4. Only on Mondays, Tuesdays, and Wednesdays.
  5. Only on Mondays and Tuesdays.

All days apart from Friday.

29. Read the following statements, and then analyze which conclusions logically follow:


  • Some roads are highways.
  • Some highways are airstrips.
  • Some airstrips are spaceports.
  • Some spaceports are islands.

Here is a list of conclusions that may or may not logically follow from the statements above:

  1. Some islands are not airstrips.
  2. All spaceports being roads is a possibility.
  3. All islands being highways is a possiblity.
  4. Some airstrips are definitely roads.

Which of the above conclusions logically follow?

  1. A and B
  2. B and C
  3. C and D
  4. Only B
  5. Only D

B and C. Both cases are possibilities, therefore they logically follow.

Logic IQ question 29

30. Jenny keeps marbles in three jars.

Logic IQ question 30

There is a blue jar, a purple jar and a green jar, sitting in a row in her room.

Until yesterday there were twice as many marbles in the green jar, than in the purple jar.

This morning, Jenny removed 3 marbles from the middle jar and gave them to a friend as a gift.

She then removed half of the remaining marbles from the middle jar and placed them into the blue jar.

What color is the middle jar?

  1. Blue
  2. Purple
  3. Green
  4. Not enough information

It's not the blue jar, since marbles were taken from the middle jar and placed into the blue jar. This leaves purple and green.

Only an even number of marbles can be split in half.

After removing 3 marbles, the remaining marbles must be capable of being split into half (even number).

Therefore, prior to removal, there must have been an odd number of marbles.

Prior to removal we know that just the green jar contained an even number of marbles. Therefore the middle jar is purple.