math tricks

How to square a number ending with 5 within seconds

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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.

Square a number ending with 5 within seconds

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

Examples to find square of a 2 digit number ending with 5

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

Example 1:35²=?
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 x 4=12).which is the 1st digit of the answer.

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

Ans  35²= 1225

Example 2:25²=?
Step 1: 2 is the ten’s digit in the given number 25.
Immediate next number to 2 is 3.
Hence,by multiplying 2 & 3 we get 6(2 x 3=6).which is the 1st digit of the answer.

Step 2: Now putting 25 next to 6 we get the answer as 625.

Ans  25²= 625

Example 3:65²=?
Step 1: 6 is the ten’s digit in the given number 65.
Immediate next number to 6 is 7.
Hence,by multiplying 6 & 7 we get 42(6 x 7=42).which is the 1st digit of the answer.

Step 2: Now putting 25 next to 42 we get the answer as 4225.

Ans  65²= 4225

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

Examples to find square of a 3 digit number ending with 5

Example 1:125²=?
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 x 13=156).which is the 1st digit of the answer.

[To multiply a 2 digit by 2 digit number when ten’s digit of both numbers is 1 you can apply below 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 x 3=6)]

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

Ans 125²= 15625

Example 2:135²=?
Step 1: 13 is the ten’s digit in the given number 135.
Immediate next number to 13 is 14.
Hence,by multiplying 13 & 14 we get 182(13 x 14=182).which is the 1st digit of the answer.

Step 2: Now putting 25 next to 182 we get the answer as 18225.

Ans 135²= 18225

Example 3:145²=?
Step 1: 14 is the ten’s digit in the given number 145.Immediate next number to 14 is 15.
Hence,by multiplying 14 & 15 we get 210(14 x 15=210).which is the 1st digit of the answer. Apply the below trick to multiply quickly
https://www.yobankexams.com/2014/01/shortcut-to-multiply-any-2-digit-number-by-15.html
Step 2: Now putting 25 next to 210 we get the answer as 21025.

Ans 145²= 21025

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