Shortcut to square any number from 30 to 79 mentally in seconds is now possible for all aspiring candidates writing different competitive exams. It is always better to have some math tricks handy when you are planning to take any arithmetic aptitude test either in the competitive exams such as Bank exams,CAT,MAT.
Another easy trick to find square of the numbers between 30 to 79 is to take a common base as 50 and see how far the number is from 50.This method works well when the number is very close to 50.
Shortcut to square of number from 30 to 79 steps
Step 1:Find how many more or less the given number is from 50.
Step 2:Add the number to 25 if more than 50 or subtract the number from 25 if less than 50.
Step 3:Then find the square of the number added or subtracted and put next to the result arrived at in step 2.
Let us now apply the trick that we learnt in the example below
Examples
Example 1:Find the square of 52 in 5 seconds
52²=?
Step 1: We see that the given number is 2 more than 50.
52-50=2
Step 2: Here we notice that the given number is more than 50 so we add 25 as follows
25+2=27
Step 3: Now we find the square of the number added(2)
22=4
22=4
putting the result obtained in step 3 next to the result obtained in step 2 after adding a 0 before it as it is a single digit,
we get, 2704
Ans: 52²=2704
Example 2:Find the square of 37 in 5 seconds.
37²=?
Step 1: We see that the given number is 13 less than 50
that is 50-37=13
Step 2: Here we notice that the given number is less than 50 so we subtract 25 as follows
25-13=12
Step 3: Now we find the square of the number subtracted(13)
we get, 132=169
put the result obtained in step 3 next to the result obtained in step 2 as shown below. And carry forward hundreth place digit to step 2.
we get,1269
Step 4:Add carry forward from step 3 to result obtained in step 2.
we get, 12+1=13
Ans: 37²=1369
Example 3:Find the square of 54 in 5 seconds
54²=?
Step 1: We see that the given number is 4 more than 50.
54-50=4
Step 2: Here we notice that the given number is more than 50 so we add 25 as follows
25+4=29
Step 3: Now we find the square of the number added(4)
42=16
42=16
putting the result obtained in step 3 next to the result obtained in step 2
we get, 2916
Ans: 54²=2916
See how quickly you can square 54,49,53,51,48,32,57,59,64,67,72.Give it a try….
Also Read
Shortcut to square any number from 20-29
Shortcut to square any number from 10-19
it is very helpful …. thanks