Yesterday’s Problem:
The sum of ages of 5 children born at the intervals of 3 years each is 50 years. What is the age of the youngest child?
Answer:
4 Years.
Explanation: Let the age of the youngest child be x: The ages of the five children are thus: x, (x + 3), (x + 6), (x + 9) and (x + 12) years. This means:
x + (x + 3) + (x + 6) + (x + 9) + (x + 12) = 50
To solve: 5x = 20 and x = 4.
The youngest child (x) is thus 4 years old.
Today’s Math Problem:
The difference between a two-digit number and the number obtained by interchanging the positions of its digits is 36. What is the difference between the two digits of that number?
Remember: It really does not matter whether you solve this correctly. Simply thinking through possible solutions creates new neural networks – and that is the point of these mind exercises.