Expert: Josh - 5/11/2006

Question
Hello:

I have a question that I am having some difficulty solving. Perhaps you can find the solution. It is as follows:

John is 5 years older than Thomas. Thomas is 2 years younger than Harry
and 1 year older than Richard. John is how much older than Harry?

I do not know why the "1 year older than Richard" is significant for determining the answer.

I thank you for any helpful reply that you may send to me.


Answer
Hello,

I suggest that we assign a variable to each of the unknown and relate the ages through algebraic expressions.

Let "j", "t", "h", "r" be the age of John, Thomas, Harry and Richard, respectively.

From the information given, we know that
j=t+5  ...[#1]
t=h-2  ...[#2]
t=r+1  ...[#3]

You're quite right. [#3] is irrelevant.
To relate John and Harry's age, we need to express "j" in terms of "h". Substituting [#2] into [#1], we have
j=t+5=(h-2)+5=h+3.

Therefore, John is three years older than Harry.