Aptitude - Numbers - Discussion
Discussion Forum : Numbers - General Questions (Q.No. 5)
5.
1397 x 1397 = ?
Answer: Option
Explanation:
| 1397 x 1397 | = (1397)2 |
| = (1400 - 3)2 | |
| = (1400)2 + (3)2 - (2 x 1400 x 3) | |
| = 1960000 + 9 - 8400 | |
| = 1960009 - 8400 | |
| = 1951609. |
Discussion:
55 comments Page 3 of 6.
Madhu said:
1 decade ago
Just that is a formula:
(a-b)^2 = a^2 + b^2 + 2ab in the same way
(1400-3)^2 = 1400^2 + 3^2 + 2*1400*3
(a-b)^2 = a^2 + b^2 + 2ab in the same way
(1400-3)^2 = 1400^2 + 3^2 + 2*1400*3
Kriti said:
1 decade ago
Well, the given explanation is in the form of (a-b) ^2=a^+b^-2ab. Which is easier to solve.
Jaishanth said:
8 years ago
@Kabita.
We should just minus the 3 from 1400 to make the formula=(a-b)^2.
1397=(1400-3).
We should just minus the 3 from 1400 to make the formula=(a-b)^2.
1397=(1400-3).
Sharon said:
1 decade ago
Dear Tamil your explanation is good.
But please explain me from where do that 3 comes?
But please explain me from where do that 3 comes?
Sindu said:
8 years ago
1397*1397= (1397*1000)+(1397*400)-(1397*3) = 1951609.
Split 1397 as (1000+400-3).
Split 1397 as (1000+400-3).
Sonal said:
1 decade ago
@Sravani.
How can you calculate the number of 779?
Can you explain it again?
How can you calculate the number of 779?
Can you explain it again?
Malik said:
1 decade ago
Can someone make me understand this line = (1400)2 + (3)2 - (2 x 1400 x 3) ?
Ajay said:
1 month ago
@Pramod.
Very clear and understanding. Thanks for your explanation.
Very clear and understanding. Thanks for your explanation.
Ajith said:
8 years ago
@Isha.
Whether it is applicable to all type of problems like this?
Whether it is applicable to all type of problems like this?
Nagarjuna goud said:
9 years ago
Hi @Sravani.
I did not understand your answer how it came?
I did not understand your answer how it came?
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