Math Is Fun Forum

great_math

Member

Registered: 2008-10-07

Posts: 5

Re: 10 second questions

#770. How many zeros would 25! (factorial of 25) end in?

No. of zeros at the end of

So no. of zeros at the end of 25!=

Last edited by great_math (2008-11-06 00:27:06)

Jai Ganesh

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Registered: 2005-06-28

Posts: 48,385

Re: 10 second questions

Solution to #770:

great_math, I am not too sure about the valadity of your formula.
Your answer is, however, correct!
Excellent!

#771. What is the sum of all the natural numbers less than 100 divisble by 3?

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Jai Ganesh

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Re: 10 second questions

#772. Fill in the Magic square with numbers from 1 to 9 such that the side totals and diagonal totals equal 15.

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

JaneFairfax

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Registered: 2007-02-23

Posts: 6,868

Re: 10 second questions

Last edited by JaneFairfax (2008-11-10 01:04:23)

Jai Ganesh

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Posts: 48,385

Re: 10 second questions

Solution to #772:

Excellent, JaneFairfax!

#773. What is the sum of all prime numbers betwen 1 and 30, both numbers included? Is the resultant a prime number?

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Jai Ganesh

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Registered: 2005-06-28

Posts: 48,385

Re: 10 second questions

#774. Is 10001 a prime number?
(Additional 20 seconds allowed for answering this question)

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Jai Ganesh

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Registered: 2005-06-28

Posts: 48,385

Re: 10 second questions

#775. By selling 55 cups, a person gains an amount equal to the selling price of 11 cups. Find his profit percentage.

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Jai Ganesh

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Registered: 2005-06-28

Posts: 48,385

Re: 10 second questions

#776. What is the value of

?

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Jai Ganesh

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Registered: 2005-06-28

Posts: 48,385

Re: 10 second questions

#777. What is the value of

?

#778. Without actual multiplication, find the value of 103 x 97.

#779. Factorize:- 49a² + 70ab + 25b².

#780. Factorize:-

.

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Jai Ganesh

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Registered: 2005-06-28

Posts: 48,385

Re: 10 second questions

#781. What is the square root of 176400?

#782. What is the square root of 39690000?

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Jai Ganesh

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Posts: 48,385

Re: 10 second questions

#783. What is the value of
sinθ * cosθ * cosecθ * secθ * tanθ * cotθ when θ=45°?

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Jai Ganesh

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Re: 10 second questions

#784. What is the value of

?

#785. Find the real and imaginary parts of the following complex number:-

.

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

JaneFairfax

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Registered: 2007-02-23

Posts: 6,868

Re: 10 second questions

Jai Ganesh

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Registered: 2005-06-28

Posts: 48,385

Re: 10 second questions

Answer to #784:-
You are correct, JaneFairFax! Well done!

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Jai Ganesh

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Posts: 48,385

Re: 10 second questions

#786. Prove that

#787. If a, b, c are three consecutive natural numbers, prove that

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Jai Ganesh

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Registered: 2005-06-28

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Re: 10 second questions

#788. Find the 40th term of an Arithmetic Ptogression whose 9th term is 465 and 20th term is 388.

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Jai Ganesh

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Registered: 2005-06-28

Posts: 48,385

Re: 10 second questions

#789. Find the nature of roots of

.

#790. Find the nature of roots of

.

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Jai Ganesh

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Registered: 2005-06-28

Posts: 48,385

Re: 10 second questions

#791. Find the equation of the straight line passing through the intersection of 3x+4y=17 and 4x-2y=8 and perpendicular to 7x+5y=12.

#792. Find

if x=at² and y = 2at

#793. Find

if

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Jai Ganesh

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Registered: 2005-06-28

Posts: 48,385

Re: 10 second questions

#794. Two numbers are in the ratio 3:4. If 6 be added to each term of the ratio, then the new ratio will be 4:5. Find the numbers.

#795. What are 'relatively prime' numbers?

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Jai Ganesh

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Posts: 48,385

Re: 10 second questions

#796.If U={1,2,3,4,5,6,7} where U is the Universal Set, A = {1,2,3}, B = {2,3,4} and C = {3,4,5,6}, verify that

and

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Jai Ganesh

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Posts: 48,385

Re: 10 second questions

#797. Prove that the two diagonals of a rhombus divide it into four congruent triangles.

#798. For two triangles to be similar, would it be enough if any two sides are proportional and any one angle of one triangle is equal to that of another?

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Jai Ganesh

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Registered: 2005-06-28

Posts: 48,385

Re: 10 second questions

#799. There are six vacancies in an Office. If 8 men and 5 women offertehmselves for the job, in how many ways can the posts be filled, if there's a condition that the vacancies should go half to men and half to women?

#794. If

, find

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Jai Ganesh

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Registered: 2005-06-28

Posts: 48,385

Re: 10 second questions

#795. The vectors

and

are perpendicular when

(1)a=2, c=3, b=-4
(2)a=4, b=4, c=5
(3)a=4, b=4, c=-5
(4)a=-2, b=3, c=4

#796.The slope of the normal to the curve y=3x² at the point where the x-coordinate is 2 is __________.

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Jai Ganesh

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Registered: 2005-06-28

Posts: 48,385

Re: 10 second questions

#797. Compute A+B and A-B if

and

#798.Find the product of A and B if

and

.

#799. Find

if

.

#800. Identify if matrix A given below is a singular matrix.

.

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Jai Ganesh

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Registered: 2005-06-28

Posts: 48,385

Re: 10 second questions

#801. Find the angle between the vectors

and

.

#802. What is the value of

?

#803.For what value of m are the two given vectors perpendicular to each other?

and

.

#804. If

, then what is the velocity when the acceleration is zero?

#805. What is the value of

?

#806.Express the complex number

in the polar form.

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.