I need to know if thee is some formula for this type of questions. plz help
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InfinityToucher8:
96 or 97?
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Two Digit palindromes should contain both digits same.
So,total no of two digits palindromes = 9 (11,22,33,...99)
To find 3 digit palindromes we will go with Permutations.
To become a 3 digit number palindrome 1st and 3rd digit should be same..(1_1,2_2,3_3.....9_9)
So this place can be filled in 9 way (number must not start with 0)
Second place can be filled with 10 ways (_0_,_1_,_2_,...._9_)
So total no of three digit palindromes =9×10=90
Now,1001 is the only one four digit palindrome between 10 and 1010
So, Total = 9 + 90 + 1 = 100
So,total no of two digits palindromes = 9 (11,22,33,...99)
To find 3 digit palindromes we will go with Permutations.
To become a 3 digit number palindrome 1st and 3rd digit should be same..(1_1,2_2,3_3.....9_9)
So this place can be filled in 9 way (number must not start with 0)
Second place can be filled with 10 ways (_0_,_1_,_2_,...._9_)
So total no of three digit palindromes =9×10=90
Now,1001 is the only one four digit palindrome between 10 and 1010
So, Total = 9 + 90 + 1 = 100
I've edited !
May i ask these questions you're asking are of which class
these questions are from competitive exams.
class ?
Well, i also give competitive exams thats why
ok these rfrom various exams
-_- i asked which grade ? class ? std ?
i have a group of frndz on whatsapp. they upload various question they get troubled from
Ohk ohk
:-)
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