Post mathematic related questions here
OP
rst
Youngling
Re: mathematic related questions
Your method is absolutely right
But as diameter is 1mm
so it will be
1/1000 * length = 1
length = 1000 m
these are questions of various competitive examinations based on 10 th level
Your method is absolutely right
But as diameter is 1mm
so it will be
1/1000 * length = 1
length = 1000 m
these are questions of various competitive examinations based on 10 th level
Niilesh
Padawan
Re: mathematic related questions
Solution -
Note: The answer should be a multiple of 7 so that that next day will be Friday
No. of days possible between two 13ths of months in a leap year - 29,30,31
Now its basically hit and trial
Case 1 - in one month
29,30,31 all are not divisible by 7
Case 2 - in two months
29+31= 60 not divisible by 7
30+31= 61 not divisible by 7
31+31= 62 not divisible by 7
Case 3- in three months
30+31+30= 91
31+30+31= 92 not divisible by 7
31+29+31= 91
29+31+30= 90 not divisible by 7
So ans - 91
Solution -
Note: The answer should be a multiple of 7 so that that next day will be Friday
No. of days possible between two 13ths of months in a leap year - 29,30,31
Now its basically hit and trial
Case 1 - in one month
29,30,31 all are not divisible by 7
Case 2 - in two months
29+31= 60 not divisible by 7
30+31= 61 not divisible by 7
31+31= 62 not divisible by 7
Case 3- in three months
30+31+30= 91
31+30+31= 92 not divisible by 7
31+29+31= 91
29+31+30= 90 not divisible by 7
So ans - 91
OP
rst
Youngling
Re: mathematic related questions
your answer is better than hit and trial method
But in your answer
I didn't understand last three lines or steps
for example
If A ≥ R
B ≥ R
can we say A ≥ B ??
your answer is better than hit and trial method
But in your answer
I didn't understand last three lines or steps
for example
If A ≥ R
B ≥ R
can we say A ≥ B ??
Niilesh
Padawan
Re: mathematic related questions
I am not sure though
Alternate method -
A.M = GM when all the no.s are equal(let it be 'a')
now 7a=21 => a=3
So ans = 7*9/7 = 9
Its just organized hit and trial
I think it is valid if A is variable and B is a constant( max value of R is B and since A ≥ R=> A ≥ B )
I am not sure though
Alternate method -
A.M = GM when all the no.s are equal(let it be 'a')
now 7a=21 => a=3
So ans = 7*9/7 = 9
OP
rst
Youngling
Re: mathematic related questions
------------------------------------------------
NEW OBJECTIVE QUESTION
Also plz explain your answer
(Also you can ask your mathematics related questions or queries
we will try to solve them)
I am also not sure
------------------------------------------------
NEW OBJECTIVE QUESTION
Also plz explain your answer
(Also you can ask your mathematics related questions or queries
we will try to solve them)
Last edited:
OP
rst
Youngling
Last edited:
Niilesh
Padawan
Re: mathematic related questions
Answer - (B)(√2a)
Solution - Distance b/w vertex and centre will be equal to 'a'(connect the centre to two consecutive vertex, it will be isosceles triangle with one angle 60 degree, so it will be equilateral)
Now apply Pythagoras theorem
@rst
Did you really understood the proof that vignesh quoted?
Answer - (B)(√2a)
Solution - Distance b/w vertex and centre will be equal to 'a'(connect the centre to two consecutive vertex, it will be isosceles triangle with one angle 60 degree, so it will be equilateral)
Now apply Pythagoras theorem
@rst
Did you really understood the proof that vignesh quoted?
OP
rst
Youngling
Re: mathematic related questions
Great explanation
I didn't understand much about both a & b are even
" if you look at a/2, b/2 then one easily sees that both
(a/2)^2 + 6(b/2)^2
(b/2)^2 + 6(a/2)^2
are squares (since the squares a^2 + 6b^2 and b^2 + 6a^2 are both even, hence divisible by 4)
This contradicts the minimality of our original solution."
I don't where is "vignesh" ??
He should explain this fact
Great explanation
his proof is same as I explained with example
I didn't understand much about both a & b are even
" if you look at a/2, b/2 then one easily sees that both
(a/2)^2 + 6(b/2)^2
(b/2)^2 + 6(a/2)^2
are squares (since the squares a^2 + 6b^2 and b^2 + 6a^2 are both even, hence divisible by 4)
This contradicts the minimality of our original solution."
I don't where is "vignesh" ??
He should explain this fact
Last edited:
OP
rst
Youngling
Re: mathematic related questions
yeah
(a/2)^2 + 6(b/2)^2 is not always a perfect square
take example
a=2
b=2
then (a/2)^2 + 6(b/2)^2= 1+6=7
which is not perfect square
I hope both a & b are even case is now clear to you
------------------------------------------------
NEW OBJECTIVE QUESTION
Also plz explain your answer
(Also you can ask your mathematics related questions or queries
we will try to solve them)
yeah
(a/2)^2 + 6(b/2)^2 is not always a perfect square
take example
a=2
b=2
then (a/2)^2 + 6(b/2)^2= 1+6=7
which is not perfect square
I hope both a & b are even case is now clear to you
------------------------------------------------
NEW OBJECTIVE QUESTION
Also plz explain your answer
(Also you can ask your mathematics related questions or queries
we will try to solve them)
Last edited: