Half my age?

If I understand the question.

Someone who is younger than you is half your age exactly once during their lifetime (assuming neither of you die first).

The number can't be less then 1. The number can't be more than 1.

The answer to your last question is no. Not more than once in a lifetime practically speaking.

The answer to your first question is because next year one person is 35 and the other is 18 but there will still only be 17 years between you no matter how old you both get.

I understand the number changes,but if I am half your age this year why am I not every year.

Because the year one person is 34 and the other person is 17 is the only year that being 17 years younger equals one half.

You can do the experiment yourself in your kitchen. Put two cups of water in one measuring cup and one cup of sugar in another. The sugar is half as much volume as the water yes? Now add a cup of water to the water and a cup of sugar to the sugar. Now you have three cups of water and two cups of sugar. The sugar is two thirds the volume of the water. To keep the volume of sugar at half that of the water you would add only 1/2 cup of sugar to the full cup of water.

The only way to keep yourself at half somebody else's age is to age at a different rate than the other person. If the other person ages two years to your one, then next year you would still be half his age. The ratios change with the amounts added or subtracted. In other words you each age one full year each year....you can't age half a year while he ages a whole year which would be necessary to keep the ratios the same.

Because the ages increase in a linear fashion, but the ratio of the two ages does not.

A person younger than you is half your age when her age is equal to the difference between your ages.

If you are 34 and I am 17, then you were born 17 years before I was.

Every year you age one year and I age one year... so you will always be born 17 years before I was.

Keep the numbers simple.

Say you have two children, one is 2 and the other is 4.

What happens next year? They become 3 and 5. Not 3 and 6.

You could apply for a job at the Bank of America.

half my age

once you turn 36, it's an excellent way to choose the age of your dates

Just to state it simply, in order to STAY half someone's age, you would have to add 1 year every year and they would have to somehow add 2. That would be difficult to do

So,

34 = 17 x2

Next year,

35 18x2.

Cycloptichorn

Let's says you're 45 and she's 15. You're three times her age. In 15 years you will be 60 and she will be 30. Now you're only twice her age. How long before you're the same age...?

The general rule I have heard for the age of creepiness is:
C = A/2 + 7

Where A is your age, and C is the lower limit you can date without being creepy.

(This means a 36 year old shouldn't go below 25).

thank you for the reply.

You're welcome. I have one of those wierd minds that asks questions like that too--just to be able to formulate an asnwer is like solving a puzzle sometimes. It's fun.

Let's say we have 2 people who's ages are different.
The difference in their ages will always be some fixed non-zero number of years. Let's call that number D.
Let's call the older one's age at any time O.
Let's call the younger one's age any time Y.
As long as both are alive, the older one's age will always be the younger one's age plus D years.
This can be expressed as follows:
O = Y + D (This will always be true, as long as both are alive.)
We want to find out the point at which the older one is twice as old as the younger. This can be expressed as:
O = 2Y (Older equals twice the younger)
Since the first equation (O = Y + D) is ALWAYS true, we are looking for the point at which BOTH are true.
That is, the point at which
O = Y + D AND O = 2Y
or
Y+D = 2Y
or
2y-y = D
or
Y = D
Therefore, when the older is twice as old as the younger, the younger one's age will be equal to the difference between their ages.
For example, if the difference between their ages is 10 years, then the older one will be twice as old as the younger when the younger is 10 years old (and the older is 20); and only then.