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 1 of 6.
Ajay said:
1 month ago
@Pramod.
Very clear and understanding. Thanks for your explanation.
Very clear and understanding. Thanks for your explanation.
ABD said:
4 months ago
1397 = 1 + 3 + 9 + 7 = 20.
1397 = 1 + 3 + 9 + 7 = 20.
20 * 20 = 400 = 4 + 0 + 0 = 4.
From options
A) 1951609 = 1 + 9 + 5 + 1 + 6 + 0 + 9 = 31,
3 + 1 = 4.
4 = 4. Hence ANSWER.
1397 = 1 + 3 + 9 + 7 = 20.
20 * 20 = 400 = 4 + 0 + 0 = 4.
From options
A) 1951609 = 1 + 9 + 5 + 1 + 6 + 0 + 9 = 31,
3 + 1 = 4.
4 = 4. Hence ANSWER.
(34)
Timothy Mayanja said:
2 years ago
Thank you everyone for explaining the answer.
(9)
Shivam said:
4 years ago
1397 * 1000 = 1397000,
1397 * 300 = 419100,
1397 * 90 = 125730,
1397 * 7 = 9779.
1397000 + 419100 + 125730 + 9779 = 1951609.
1397 * 300 = 419100,
1397 * 90 = 125730,
1397 * 7 = 9779.
1397000 + 419100 + 125730 + 9779 = 1951609.
(101)
Ashish Thakor said:
4 years ago
Thank you everyone for giving the best explanations.
(7)
Jyotirban Pandey said:
5 years ago
How did 1400 come?
(4)
Nikita said:
5 years ago
How 1400 came? Please explain.
(5)
Pritam said:
6 years ago
Step-1: Do the sum of the digits of multiplicands then multiply both.
Step-2: If the number comes in two-digit add them.
Step-3: Add all the digits of answer untill it becomes a single digit number.
15^2 = 225
1+5 * 1+5 = 2+2+5
6 * 6 = 9
36 = 9
3+6 = 9
9 = 9
So, the answer is 225.
Step-2: If the number comes in two-digit add them.
Step-3: Add all the digits of answer untill it becomes a single digit number.
15^2 = 225
1+5 * 1+5 = 2+2+5
6 * 6 = 9
36 = 9
3+6 = 9
9 = 9
So, the answer is 225.
(11)
Sagar said:
6 years ago
@Aruna.
Easy, thanks for solving it.
Easy, thanks for solving it.
(2)
Deepmars said:
6 years ago
Good explanation, thanks @Pramod.
(2)
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