Thursday, August 30, 2007

Mental Arithmetic

As I was chatting with my cousin Bertha, age 92, this morning we tried to do some arithmetic mentally. I mentioned that a champion runner could run a mile in four minutes.

The "four minute mile" had been a goal of runners for a long time, and was achieved finally.  What we tried to do, in our heads, was figure out how many miles per hour this runner achieved.

It got to be funny, we two geniuses trying to reason it out.  First Bertha said,  "A mile in four minutes is a quarter of a mile an hour." That almost sounded reasonable, for a moment.

"No," I countered.  "That is a quarter of a mile per minute. What is a quarter of a mile per minute in miles per hour?"

"There are sixty minutes in an hour," said Bertha, "multiply four times sixty. Two hundred forty."

"Nobody can run two hundred and forty miles per hour," I wailed.

We both laughed.

Later at breakfast, I worked out how many miles per hour a four minute mile runner is traveling-- in my head.

Now, I will leave it up to you to work out, in your head, OR on paper, OR with a calculator.  Your choice.


garnett109 said...

i think  the answer is 15 miles per hour

ggjack7 said...

I was never any good with reasoning problems, too taxing on the brain LOL give me a column of figures to add and I'll do it in a flash.

tendernoggle said...

15? 1 mile = 4 minutes....60 minutes in an hour divided by each 4 minute mile  = 15 miles.
love ya,

jckfrstross said...

no clue math is not my strong point lol


jmorancoyle said...


valphish said...

Well it's 15 mph.  That isn't too difficult.  I figured it out BEFORE coffee. LOL  Hugs! xox