Mathematics - 5 December 2007

How much work is done in raising a bucket of concrete (1800 kg) to a point 20 m above the ground? (weight= mass x gravity)

please show how you did it

2007-12-05 13:16:24 · 4 answers · asked by garyeestra2 1

A couple wants to invest up to $20000. They can purchase a type A bond yielding 9.75% return and a type B bond yielding a 14.5% return on the amount invested. They also want to invest at least as much in the type A bond as in the type B bond. They will also invest at least $10000 in type A and no more than $14000 in type B bond.
How much should they invest in each type of bond to maximize their return?

Let x be the amount invested in type A bond and y the amount invested in type B bond.

a) Write the objective function to be maximized.
P =

b) List the corner points of the feasible region.
Corner points:

c)Determine the amount to be invested in each bond to maximize the return and determine the maximum return:
Amount to be invested in type A bonds: $
Amount to be invested in type B bonds: $
Maximum return is: $

2007-12-05 13:15:08 · 1 answers · asked by timz11 1

SOLVE: X^3-9X^2=0

2007-12-05 13:14:10 · 9 answers · asked by Mio 2

2007-12-05 13:12:57 · 71 answers · asked by PJ 1

plz. explain how to do it. I'm fine with just the formulas but would appreciate if everything was solved. :P


A ramp could be used to raise the concrete 20 m.
a) How much work would be required if the ramp formed at an angle 30 degrees with the horizontal?
b) How long would the ramp be?
c) How much force would be required?
(The component of the force // to the ramp.)
(Neglect friction)

2007-12-05 13:08:55 · 1 answers · asked by garyeestra2 1

2007-12-05 13:05:18 · 2 answers · asked by Anonymous

I'm curious about the importance of the number 64......in "the 64 dollar question"......why 64 in the first place?

2007-12-05 13:03:11 · 1 answers · asked by oj_scott2002 1

its something for math homework and it confusing!! please help!!!

2007-12-05 13:01:05 · 6 answers · asked by Anonymous

A laboratory sample consists of a mixture of two radioactive substances, both of which decay into inert gases which evaporate into the air. The initial composition of the sample by weight is 40% of substance A and 60% of substance B and the initial weight of the sample is 297 grams. After 7 days the sample weighs 124.419451315581 grams and after 14 days it weighs 55.0505357006202 grams.
What is the half-life of substance A?
What is the half-life of substance B?
What will the sample weigh after 25 days?

2007-12-05 12:59:27 · 2 answers · asked by Anonymous

so i know that you startout by solving for the intersection points which is
x^2 - 2x = x + 4
x^2 - 2x - x + 4 = 0
(x - 4)(x + 1)=0
x = 4, -1

top= x + 4
bottom=x^2 +2x

then i solve ofr the area
A= ∫ (top - bottom) dx
A=∫ (x + 4 - x^2 +2x)dx
= ∫ (-x^2 + 3x + 4)dx
= -x^3/3 + 3x^2/2 + 4x

then i plug in b into F and a into F and subtract to get the area

the answer i get is 383/8 which is wrong.. so i dont really see what i'm doing wrong.

2007-12-05 12:56:08 · 2 answers · asked by Anonymous

3z^2 + 24z + 45

2007-12-05 12:51:40 · 5 answers · asked by Roar 1

Ok lets say you hafta find three consecutive EVEN integers for 147
You would do:
n+n+2+n+4=147
then
3n+6=147
then subtract six
3n=141
then divide 3
n=47
ok so 47 isnt even, would you just go up one and write 48, 50, and 52? Help please!!

2007-12-05 12:45:13 · 8 answers · asked by Anonymous

when using the distance formula, does it matter which point is (x,y) and which point is (x^2,y^2)

how can you make an estimate of a certain area more accurate?

2007-12-05 12:41:32 · 5 answers · asked by skatebaker416 1

What is the greatest possible values of these integers?

2007-12-05 12:35:39 · 18 answers · asked by Maddy505 1

how do you simplify square roots?

i know you have to take factors out of the square root symble and all of that but not exactly.
please help

2007-12-05 12:31:58 · 2 answers · asked by Americanito 1

How do you get it into parametric form?

2007-12-05 12:31:46 · 1 answers · asked by bentheredonethat122 2

i want to know how 2 solve inequalities. lets use this problem in an example...

6+11x >-60

and just so i can get the hang of it...

-26 < 4 - 5x

help with these would be great. thanx :]

2007-12-05 12:26:48 · 8 answers · asked by smartiechick16 2

2007-12-05 12:24:24 · 7 answers · asked by Maddy505 1

2007-12-05 12:23:44 · 4 answers · asked by Anonymous

Let f be a strictly increasing function on the interval [0,1]. Can the range of f ever consist of irrational numbers only?

2007-12-05 12:22:49 · 7 answers · asked by moshi747 3

2007-12-05 12:21:21 · 6 answers · asked by Anonymous

2007-12-05 12:19:43 · 8 answers · asked by nportales@sbcglobal.net 1

no calculators please

2007-12-05 12:19:06 · 1 answers · asked by chrys 1

FACTORING POLYNOMIALS

I have two problems.

1) Factor.

x^6 - 2x^5 + 7x^4

My answer is "not factorable." (Which means that it's impossible to factor.) My friend graded this, and she marked it wrong... Is my answer correct?

2) Factor.

m^4 + 8m^3 + 8m^2 +64m

My answer is (m + 8)(m^3 + 8m). Like I typed, my friend marked my answer wrong... Is my answer correct?

If I am wrong, please explain these two problems to me (and show your work).

If I am right, please tell me so.

Thanks for helping me!

2007-12-05 12:15:18 · 6 answers · asked by *smart smartie* 4

identify the sample size. what is your recommendation for a desired margain of error of 1% and a confidence level of 99%.

help

2007-12-05 12:12:51 · 1 answers · asked by Anonymous

what is the probablitity ..
you roll a blue number cube and a green number cube. Find the probability


P(blue and green less than 7)

2007-12-05 12:08:31 · 2 answers · asked by Anonymous

I have a math test on thursday on identities and equations but i have trouble doing it, if you guys could help, really appreciate it, ill list some questions here and you can explain to me step by step how it works. thanks

Solve each quation algebraically for 0 < x < 2pie. Express roots in exact forms..
Cos(square)x - sin(square)x = 1
Sin(square)x - cos(square)x = 1

Consider the identity cos(pie - x) = -cosx
verify the identity numerically, when x = pie/6
for what values of x is the identity defined?

2007-12-05 12:08:26 · 1 answers · asked by playpwnsu 2

((solving equations-variables on both sides)) i just want to compare answers to make sure im doing it right

2007-12-05 12:07:49 · 15 answers · asked by Anonymous

2007-12-05 12:04:15 · 4 answers · asked by brunaldhino 2

The AREA (not perimiter) of a Pentagon is 800, what is the lenght of each side??....(this is not my homeowork...i don't cheat likesome people.)

2007-12-05 11:59:14 · 1 answers · asked by K-LA 3