## Terrifying Tennis Maths: The Speed of Novak Djokovic’s serve. METRIC

February 7, 2021

USA units post here.

### Could you return his serve? Do the maths!!!!!!

The ball leaves Djokovic’s racket and hits the ground 0.31 secs later.

Go here to see why this simplified calculation works!

Mathspig tested her reaction time here. TRY IT!

Mathspig’s best, best, best reaction time = O.33 sec

## Terrifying Tennis Math: The Speed of Novak Djokovic’s serve. USA units

February 7, 2021

METRIC post here.

### Could you return his serve? Do the math!!!!!!

The ball leaves Djokovic’s racket and hits the ground 0.30 secs later.

Go here to see why this simplified calculation works!

Mathspig tested her reaction time here. TRY IT!

Mathspig’s best, best, best reaction time = O.33 sec

June 26, 2017

# ………………..How much money does a popular

You will learn everything you need to know at 1 Million YouTube Views.  Now let’s do the maths!

Here are the TOP 3 YouTube Clips Ever. Their popularity is measured by Number of Views.

View here.

View here.

# 2,850,776,581 views

View here.

YouTube uses an algorithm (ie. a formula) for calculating the amount of income earnt by a clip from advertising. There are multiple issues involved including how long viewers watch the ad, the demographics (age group) and the actual sales (Retailers actually do review ad costs vs increased sales. Always. They are not idiots.)

Here is  the basic method used to calculate ad revenue for a Youtube creator. Remember, a creator must have a minimum of 10,000 hits on their channel before any revenue is paid.

Of course, pop stars use Youtube as a promotion platform. They can earn money through multiple Youtube clips, sponsors, merchandise and live perfomances. Nevertheless, it is surprising how little money is earned by each clip.

eg. ONE DIRECTION

# 521,126,151 views

View here.

## 5. Funky, Fab and Fantastic. Yeah! That’s Middle School Maths

September 20, 2016

Algebra! Many students struggle with algebra because they see no point doing it. But here is the best fun with algebra you’ll ever have. It is so counter intuitive that you have to see the algebra to believe this trick. Mathspig tried this exercise out on school teachers at her ICME 13  workshop in Hamburg and this is the result filmed – with a few lighting wobbles – on an iphone.

Detailed explanation here.