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How to square a number ending with 5 within seconds

Squaring a number ending in 5 is the easiest if you know the trick.
Number given to you can be a two digit number or three digit number or five or six digit number,

it does’n t matter.
The same trick can be applied to find the square of any number ending in 5.

Let us now discuss the steps to follow

Step 1:Multiply the ten’s digit of the given number with its immediate next number.This will be the 1st digit of the answer.

Step 2:Put 25 next to the result of step 1.
Logic behind putting 25 is that the number will always end with 5 and 5² is 25.

You get the answer

Let us find squares of numbers ending in 5 using this trick

Example 1:(35)²=?

Step 1: 3 is the ten’s digit in the given number 35.
Immediate next number to 3 is 4.
Hence,by multiplying 3 & 4 we get 12(3×4=12).which is the 1st digit of the answer.

Step 2: Now putting 25 next to 12 we get the answer as 1225.

Answer: (35)²= 1225

Now you try to square 25,45,15,55,65,75,85,95 & see how quickly you can square.  

Example 2:(125)²=?

Step 1: 12 is the ten’s digit in the given number 125.
Immediate next number to 12 is 13.
Hence,by multiplying 12 & 13 we get 156(12×13=156).which is the 1st digit of the answer.

[To multiply a 2digit by 2digit number when ten’s digit of both numbers is 1 you can apply a trick to get your answer quickly.
1st digit =1 
middle digit =add unit’s place digit of both numbers(2+3=5)
unit’s place digit=Multiply unit place digit of both numbers(2×3=6)]

Step 2: Now putting 25 next to 156 we get the answer as 15625.

Ans (125)²= 15625

Now you try to square 105,115,135,145,155,165,175,185,195 & see how quickly you can square.