## Estimate or Calculate?

” in the real world, we constantly settle for estimates, whereas mathematics — see the SAT — demands that you get the answer precisely right.” – Andrew Hacker in The New York Times article “The Wrong Way We Teach Math

Estimate or Calculate?

My answer is one of them and do it fast.

## Have Brain? Use it!

Find the area of the rectangle if the numbers show the areas of the corresponding triangles.

Find the area of the shape.

How many squares of all different sizes are on a chessboard?

## A+Click 2014 Numbers

2014 Annual Statistics

4600+ challenging problems for students in grades one through twelve;

500,000+ sessions on websites http://www.aplusclick.com and http://www.aplusclick.ru in 2014;

5’30” is the average duration of a session;

190 countries: USA 45%; India 9%; Canada 7%; Australia 5%; UK 5%;

10,000+ cities: top cities are  Brisbane, Australia; Chicago, USA; New Delhi, India;

25% visitors via mobile or tablets;

500 stars is the Best Score of the A+Click Challenge in 2014. Suhas, Bangalore, India is the best performer of 2014.

100 Best Performers of the A+Click Challenge in 2014: USA – 28%; Cambodia – 26%; India – 15%; Canada – 6%.

2,000+ people passed IQ Test; 454 people scored over 100;

100+ suggestions from users;