### Back to the Ski Slopes

Yes, we are back on the mountain and trying to work out the speed of our skiers. We remember (from a Math lesson a long time ago) that * S*peed =

*istance/*

**D***ime. It was given to us in a triangle, something like this:*

**T**To use this triangle, simply put your finger over the letter you are solving for.

If you want to know **S** for Speed, then putting your finger over **S** gives **D**/**T** (distance divided by time). If you want to solve for **D** then covering it up you have **S** · **T** or **S**peed x **T**ime.

So, out skier covers 10kms in 45min. We want to work out her speed in kms per hour, so we first have to make sure that we are dividing by hours. 45 min = 45/60 hours or 3/4 hours (three quarters of an hour). So our speed is now = 10kms/0.75hrs which equals 13.33kms. Now, she might have stopped off for hot chocolate at the warming hut and actually done a much faster speed while travelling. But that’s another math problem for another day!