Matrix Logic: The New Baby’s Relatives

Matrix logic or logic grid puzzles challenge you to figure out the characteristics of several people, using a series of clues, marking “yes” answers with an O and “no” answers with an X in a grid of boxes.  You can see an example grid in this Wikipedia article.

My 12-year-old Nicholas enjoys matrix logic almost as much as I do, so when he asked me last night to make up a matrix logic puzzle for him, I jumped at the chance.  He wanted it to have 5 people and 5 facts about each.  I challenged myself to do it with just 5 clues.

This puzzle is about 5 people who have a new baby in their family.  What is each person’s first name, last name, month of birth, day of birth, and relationship to the baby?

Get your graph paper!  Read more of this post

Anything works better when you know how to use it!

This columnist argues that teenagers shouldn’t be taught about contraception because studies show that younger, poorer, unmarried people using oral contraceptives or condoms are more likely to get pregnant than older, more affluent, married people using the same devices.  It’s an interesting attempt at logic, but it leaves out a crucial point:

Any contraceptive method that requires action by the user (that is, anything except surgery) works better when used correctly.  How do you learn to use it correctly? Read more…