Seven runners finished a race in 34, 28, 41, 37, 30, 45 and 39…

Step by step

The question

Question: find the median of 34, 28, 41, 37, 30, 45 and 39.

The median is the middle number, once the numbers are in order.

There are four choices.

First we solve it, the normal way.

Then we pick.

1 Put them in order

First we put them in order, smallest first: 28, 30, 34, 37, 39, 41 and 45.

We still have 7 numbers.

None is lost.

2 Find the middle

We cross out the smallest and the biggest, one pair at a time.

And the next pair.

And the next pair.

37 is left in the middle.

So the median is 37.

3 Pick the choice

Our answer is median = 37.

That is choice C.

4 Why not the others

A is 36.29.

Wrong: that is the mean.

B is 17.

Wrong: that is the range.

D is 38.

Wrong: averaged 37 and 39: with 7 times there is one middle time.

Let's look back.

First: put them in order.

Then: find the middle.

Then: pick the choice.

Last: why not the others.