How are you to find 2007^2 − 2006^2 without a calculator?

Like with many questions in the PAT test once you know what to do it is quite easy! To solve you can use a difference of two squares i.e. (2007-2006)(2007+2006). As the first bracket gives 1 and the second gives 4013 (by arithmetic). Therefore you get 4013*1 = 4013 

DD

Related PAT University answers

All answers ▸

How do I sketch a function from its equation without using my graphical calculator?


Two satellites are in orbit around the Earth. The first is in a geostationary orbit, the second satellite at radius half that of the first. What is the (approximate) period, in hours, of the second satellite?


How many trailing zeros are there in 100! (100 factorial)?


Estimate the radius of the moon based on a solar eclipse given the distances between the earth and the moon, the earth and the sun, and the radius of the sun.