SAT MATH HELP

Discus: SAT/ACT Tests and Test Preparation: April 2004 Archive: SAT MATH HELP
 By Shhh (Shhh) on Friday, April 30, 2004 - 02:41 pm: Edit

All these questions are from 10 real SATs 2nd edition and i have no idea how to solve them

the first one is from Nov 1996 and its a chart problem so i cant type it up. Its S7 number 7
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The second one is from the same test and same section, its number 8

Ms Clark drove from her home to the museum at an average speed of 40 m/h and returned home along the same route at an average speed of 35 m/h. If her total driving for the trip was 2 hours, how many minutes did it take Ms Clark to drive from her home to the museum?

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The third one is from the same test but section 4

number 19

If (3x^2 + 4x + 5) (3x + 6) = ax^2 + bx ^2 + cx + d
for all values of x, what is the value of c?

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The fourth one is from the same test and section

number 21

A teacher is to be assigned to teach 5 different courses in 5 different class periods on mondays. If exactly one course meets each period, how many different assignments of courses to these class periods are possible for monday?

if anyone can help me out it would be greatly appreciated

 By Brum (Brum) on Friday, April 30, 2004 - 04:44 pm: Edit

She goes the same distance there, same distance back.
d = d
rt = rt
40t = 35(2-t)
t = .93 h

.93 h (60 min / 1 h) = 56 min

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(3x^2 + 4x + 5) (3x + 6)

c is all the terms with "x" (no x^3, no x^2, no x^0)
What gives us "x"? When we do 3x * 5 and when we do 6 * 4x.

3x*5 + 6*4x = 15x + 24x = 39x
Thus, c = 39.

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First write this...

_ * _ * _ * _ * _

each of those blanks represents a class period.

in the first blank, there are 5 possible classes to put there. in the second blank, there are 4 classes we can put there (because one class has been "used up"). Then 3, then 2, then 1.

Then, multiply those. 5*4*3*2*1 = 120

(This is 5! in other words)

 By Shhh (Shhh) on Friday, April 30, 2004 - 07:47 pm: Edit

thanks, but i still dont understand the distance question :-(

 By Shhh (Shhh) on Friday, April 30, 2004 - 07:47 pm: Edit

and how do u know when to use "n!"?