Maths tips & tricks # 4: square a 2 digit number ending in 5

Prabeer (B. COM (H) CA & CS Final)   (5484 Points)

02 September 2011  

Maths Tips & Tricks # 4:Square a 2 Digit Number Ending in 5





For this example we will use 25;

  • Take the "tens" part of the number (the 2 and add 1)=3
  • Multiply the original "tens" part of the number by the new number (2x3)
  • Take the result (2x3=6) and put 25 behind it. Result the answer 625.

Try a few more;



75 squared = 7x8=56 ... put 25 behind it is 5625.







55 squared = 5x6=30 ... put 25 behind it ... is 3025. Another easy one! Practice it on paper first!