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**Devantè****Real Member**- Registered: 2006-07-14
- Posts: 6,400

67. 2*2*2*2*2*3*3*3*3*3

68. Well, I know 6! = 720, so 6! x 7 = 5040

(I knew 7! off by heart, though)

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 15,375

Devante`,

If you meant the prime factors are 2 and 3, you're right.

Your answer isn't clear.

However, for #68, your answer is perfectly correct.

Well done

Character is who you are when no one is looking.

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**Devantè****Real Member**- Registered: 2006-07-14
- Posts: 6,400

Sorry for the unclear answer, I forgot to extend on my answer. In a test, I would've lost a mark for that. :\

Yep, that's what I meant.

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**ganesh****Moderator**- Registered: 2005-06-28
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69. How many pounds is a kilogram?

70. What is an AU?

Character is who you are when no one is looking.

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**Devantè****Real Member**- Registered: 2006-07-14
- Posts: 6,400

69. 2.20462262 pounds is a kilogram.

70. AU stands for Astronomical Unit. 1 AU = 149598000 kilometers.

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**ganesh****Moderator**- Registered: 2005-06-28
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Very well done, Devante`.

Character is who you are when no one is looking.

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**Devantè****Real Member**- Registered: 2006-07-14
- Posts: 6,400

A WikiPedia article on Astronomical Units, if anyone's interested: http://en.wikipedia.org/wiki/Astronomical_unit

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**Toast****Real Member**- Registered: 2006-10-08
- Posts: 1,321

Wow... they estimated the distance to the sun with a margin of error of 30 metres!?!

o_o

Doesn't the distance change alot due to gravity?

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**mathsyperson****Moderator**- Registered: 2005-06-22
- Posts: 4,900

Indeed it does, because our orbit around the sun is slightly elliptical. But their definition of the AU is something like "the radius of an orbit around the sun that would take exactly one year for a complete revolution".

Which is kind of a technical way of saying that it's our average distance from the sun.

Why did the vector cross the road?

It wanted to be normal.

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**hkreddy7****Member**- Registered: 2006-11-13
- Posts: 5

12. 1,000,000,000

(10^9)

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**ganesh****Moderator**- Registered: 2005-06-28
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71. What is the angular velocity of the minutes hand of the clock in radians per second?

72. What is the significance of the number 746 in physics?

73. And what is the significance of the number 760 in physics?

74. How many prime numbers are there from 1 to 100?

75. And How many prime numbers exist from 1 to 1000?

Character is who you are when no one is looking.

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**mathsyperson****Moderator**- Registered: 2005-06-22
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71. π/1800

I have no idea about the others, but I'll guess that there are ~30 primes from 1 to 100 and ~250 from 1 to 1000.

Why did the vector cross the road?

It wanted to be normal.

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**Devantè****Real Member**- Registered: 2006-07-14
- Posts: 6,400

71) ((pi)/1800)

72) Approximately 746 watts (actually about 745.7) to every horsepower (hp).

73) Originally defined as one one-hundredth of the difference between the freezing and boiling temperatures of water under an atmospheric pressure that balances a **760**-mm (29.92-inch) column of mercury. Now defined as the fraction 1/273.16 of the thermodynamic temperature of the triple point of water.

74) 25 primes from 1 to 100

75) 168 primes from 1 to 100

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**Toast****Real Member**- Registered: 2006-10-08
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Nice job Devante

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 15,375

Excellent, Devante`

Character is who you are when no one is looking.

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**ganesh****Moderator**- Registered: 2005-06-28
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76) How many seconds are there in a day of 24 hours?

77) If 12 numbers is a dozen, and 144 (12 dozens) is a gross, how many would 12 grosses be?

Character is who you are when no one is looking.

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**Devantè****Real Member**- Registered: 2006-07-14
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76) 1440 x 60 = 86400

77) 144 x 12 = 1728

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**ganesh****Moderator**- Registered: 2005-06-28
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Well done, Devante`! I believe you did that within 10 seconds!

78. If 6 men can make 6 tables in 6 days, how many tables can be made by 12 men in 12 days?

79. What is 20 times the value of square root of 2 rounded off to two decimals?

80. How many zeros does a nonillion contain?

Character is who you are when no one is looking.

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**Devantè****Real Member**- Registered: 2006-07-14
- Posts: 6,400

78. It might be a trick question...maybe 12?

79. 1.41 x 20 = 28.2

80. I think 30 zeros.

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 15,375

78. You are wrong! Interesting!

79. Correct, I guess that was a sitter!

80. You think right, well done!

81. What is the measure of each angle of a regular pentagon?

82. What is 1+2+3+4+...500?

83. If five teams participate in a tournament and each team plays every other team once, how many matches are played in all?

Character is who you are when no one is looking.

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**Toast****Real Member**- Registered: 2006-10-08
- Posts: 1,321

79. 24

81. (5-2)*180/5 = 108

82. 501*250 = 125250 (sorry took longer than 10 seconds on this one )

83. I believe the formula is

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**Devantè****Real Member**- Registered: 2006-07-14
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82. I remember this question. I did it with 1 to 100 once.

501x250 = (501x1000)/4 = 125250

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**ganesh****Moderator**- Registered: 2005-06-28
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Excellent, Toast and Devante`! Well done! Don't mind if it took a second or two more!

84. How many digits does 100! contain?

85. And how many digits does 2^500 contain?

Character is who you are when no one is looking.

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**mathsyperson****Moderator**- Registered: 2005-06-22
- Posts: 4,900

Depending on where you are, the answer to 80. could also be 54 zeroes.

85. 500/log 2, rounded up.

Why did the vector cross the road?

It wanted to be normal.

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**justlookingforthemoment****Moderator**- Registered: 2005-05-26
- Posts: 2,161

78. 24 tables.

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