Arithmetic Reasoning

Probability

Yesterday I presented a probability question involving rolling a die.

What is the probability of landing on an even number when rolling a die?

  1. 1/2
  2. 1/3
  3. 2/3
  4. 5/6

Yesterday I presented a question on probability.  As an ASVAB tutor, I see the importance of preparing my students for questions on probability.  Probability is one of the subtopics that can appear on the Arithmetic Reasoning section of the ASVAB.  It is one of the 15 subtopics I cover in my book, The ASVAB Tutor’s Arithmetic Reasoning Study Guide.  Figuring out probability involves figuring out what the chances of something happening are.  To figure out the probability of landing on an even number when rolling a die, you need to figure out two things.  First, figure out how many sides are on a die.  A die has 6 sides.  Second, figure out how many of the sides are even.  There are 3 even sides on a die: 2, 4, and 6.  Now you are able to figure out the probability by creating a fraction.  The top number of the fraction would be how many sides are even.  The bottom number of the fraction would be how many total sides.  Three sides are even.  There are six total sides.  The fraction would be 3/6.  This fraction can be reduced because 3 and 6 can both be divided by 3.  The fraction would reduce to 1/2.

1/2  is the final answer.