Squaring of numbers that begin with 5

You can square any number with this trick which begins with 5 in seconds without much of calculation.

To get the left part of the answer, always add 25 to ones digit.
To get the right part of the answer, always square the ones digit.

54² = 2916

As the number to be squared begins with 5 we can use this trick.

• Add the 25 to ones digit (i.e 4)4 + 25 = 29 (left part of the answer)

• Square the ones digit4 x 4 = 16 (right part of the answer)

Answer 2916

As the number to be squared begins with 5 we can use this trick.

• Add the 25 to ones digit (i.e 2)2 + 25 = 27 (left part of the answer)

• Square the ones digit2 x 2 = 04 (right part of the answer)

Put 0 before 4 to make it a double digit number.

Answer 2704

Time for you to try