How to solve ibps bank aptitude questions in 36 seconds?

From the above table you will find squares are not ending with 2,3,7,8. But cubes are ending with 1,2,3,4,5,6,7,8,9.
We need to calculate square root of 1444.
Step 1: Split the number into two parts 14, 44 (last two digits are one part, remaining are one part); 44 is ending with 4 so the unit digit of square root ending with only 2 or 8.
2^2 = 4 ; 8^2 = 64 ;
Step 2: First part 14 is in between 3^2 to 4^2 (between 9 to 16)
so the second digit of square root is 3 or 4. In this case always you should take small number. Here small number is 3. 
Step 3: We have found one digit is 3, what is the unit digit? (2 or 8). For this, take first part which is close to 3^2 to 4^2. It is close to 4^2 (16) only. so take 8 as second digit.
Step 4: Write first part answer(3) and second part answer(2) together.Hence Answer is 38.
5. 56^2 = ?
(50+6)^2;
Step 1: 50^2 = 2500 —-(1)
Step 1: 6 x 100 = 600 —-(2)
Step 1: 6^2 = 36 —-(3)
Add step 1,2,3 Answers = 2500+3600+36 = 3136
​Answer is 3136.
​6. ∛205379

We need to find cube root of 205379, see the above table
Step 1: Split the number into two parts 205, 379 (last three digits are one part, remaining are one part); 
Note* : For square root calculations (we have splitted last two digits are one part, remaining are one part). for square and cube root we should know values from 1^2—— to 25^2,1^3—–to 10^3 are necessary​.
379 is ending with 9 so the unit digit of cube root ending with only 9.
9^3 = 729 ;
Step 2: First part 205 is in between 5^3 to 6^3 (between 125 to 216)
so the second digit of square root is 5 or 6. In this case always you should take small number. Here small number is 5. 
Step 3: We have found second digit 5, the unit digit is 9. 
Step 4: Hence Answer is 59.
7. 343 x 999 = ?
​343× 999 = ?
​Step 1: For the above calculation you just minus 1 from the number then you will get 342.
Step 2: Subtract the 342 from 999, you will get 657.
Step 3: Finally write the both step 1,step 2 answers together.342657 is the answer.                                   
​343 × 999                                                                
Step 1:  343-1= 342
Step 2:   999-342=657                         
Step 3: 342657 (Answer)
​NOTE: If no of 9’s are more than no of digits in number means just add 0’s infront of the number.(eg:00123× 99999).If no of digits in number is more than no of 9’s means dont use this technique.

We need to find cube root of 39304, see the above table
Step 1: Split the number into two parts 39, 304 (last three digits are one part, remaining are one part);
Note* : For square root calculations (we have splitted last two digits are one part, remaining are one part). for square and cube root we should know values from 1^2—— to 25^2,1^3—–to 10^3 are necessary​.
​304 is ending with 4 so the unit digit of cube root ending with only 4.4^3 = 64 ;
Step 2: First part 39 is in between 3^3 to 4^3 (between 27 to 64) so the second digit of square root is 3 or 4. In this case always you should take small number. Here small number is 3. 
Step 3: We have found second digit 3, the unit digit is 4. 
Step 4: Hence Answer is 34.
14. 74 x 76 (Type 1) (Unit digit is different, second digit is same, sum of unit digit is 10)
Step 1: second digit x (second digit + 1)
7 x (7+1) = 56 ; 
Step 2 : Unit digit x Unit digit
4 x 6 = 24 ;
Step 3 : write both step 1 step 2 answers together,
Answer = 5624.
15. 97 x 96 
Step 1 : (100-3) x (100-4)
Step 2 : (97 – 4 = 93) OR (96 – 3 = 93)
Step 3 : 3 x 4 = 12
Step 4 : write Step 2,Step 3 Answes together 9312.
Answer = 9312.