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josmiceli answered: 9651 problems
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Answer 402187 by josmiceli(9654) on 2012-08-17 22:57:21 (Show Source):
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Travel_Word_Problems/638405: a trip to washington from boston will take you 5 3/4 hours. If you have traveled 1/3 of the way, how much longer will the trip take? 1 solutions
Answer 402183 by josmiceli(9654) on 2012-08-17 22:45:02 (Show Source):
You can put this solution on YOUR website!You have 2/3 of the distance left. As long as your
speed is constant, you have  of
the time left. That is
 hrs
 minutes
You have 3 hours and 50 minutes left
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Age_Word_Problems/638254: Mary is now four times as her daughter.four years ago the product of their ages was 40 find their present ages. Thankyou 1 solutions
Answer 402083 by josmiceli(9654) on 2012-08-17 09:01:44 (Show Source):
You can put this solution on YOUR website!Let  = Mary's age now
Let  = Daughter's age now
given:
(1) 
(2) 
------------------------
Substitute (1) into (2)
(2) 
(2) 
(2) 
(2) 
(2) 
(2)

Daughter's age must be positive, so
the Daughter is 6
and, since
(1) 
(1) 
(1) 
The Mother is 24
--------------
check answers
(2) 
(2)
(2) 
(2) 
OK
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Age_Word_Problems/638224: In three more years, Katrina's mother will be six times as old as Katrina was last year. When Katrina's present age is added to his grandfather's present age, the total is 57. How old is each one now? 1 solutions
Answer 402080 by josmiceli(9654) on 2012-08-17 08:48:35 (Show Source):
You can put this solution on YOUR website!Let  = Katrina's age now
Let  = Mother's age now
Let  = Grandfather's age now
given:

------------
Some information must be missing. You've
got 3 unknowns but only 2 equations, so
it can't be solved as it stands.
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Triangles/638246: One of the angle of a triangle is 65. Find the remaining two angles if their difference is 25 1 solutions
Answer 402076 by josmiceli(9654) on 2012-08-17 08:19:57 (Show Source):
You can put this solution on YOUR website!Call the unknown angles  and 
The angles of a triangle always add up to 180 degrees, so
(1) 
also given is
(2) 
---------------
(2) 
Substitute this into (1)
(1) 
(1) 
(1) 
(1) 
and, since
(2) 
(2) 
(2) 
The remaining angles are 45 and 70 degrees
check:
(1) 
(1) 
(1) 
OK
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Travel_Word_Problems/637973: A bus is 13 kilometers from town, going away at 80km/h. At the same moment a car leaves town going the same direction as the bus, at the same speed.
x = number of hours the car and bus have been going
80x = car's distance from town
13 + 80x = bus's distance from town
After how long will the bus's distance be twice the car's distance?
I already know that it will happen when the bus is 26 km from town, and the car is 13 km from town, meaning they've each traveled 13km. At 80km/h this means it will happen at 13/80 of an hour, or 9.75 minutes. But I can't figure out how to write an algebraic equation showing this. Here is what I tried, and I get a negative number:
80x = 2 * 80x + 13
80x - 13 = 160x
-13 = 80x
-13/80 = 80x/80 1 solutions
Answer 401947 by josmiceli(9654) on 2012-08-16 11:40:11 (Show Source):
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Proportions/637892: Debbie and kevin share profits in the ratio of 4:3 they admit jessie into the partnership for 1/5 share of the profits.
Debie and Kevin will continue to share profits in the same ratio as between themselves.
What will be the profit sharing ratio of the new partnership of Debbie, Kevin and Jessie? 1 solutions
Answer 401934 by josmiceli(9654) on 2012-08-16 00:51:07 (Show Source):
You can put this solution on YOUR website!They keep the ratio of profit at 4:3
J has 1/5 share, so D and K have
4/5 share together.
D has  share
K has  share
J has  or  share
-----------------------------
Note that 
as it should
The ratios now are:
D:K:J = 16:12:7
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Money_Word_Problems/637539: Help on this problem would be greatly appreciated!
A village wants to build a community center that is projected to cost 1.2 million dollars. Cost per resident is increased by $3 as it is discovered that there are 225 fewer residents than when planning began 2 years ago. What is the revised cost per resident? 1 solutions
Answer 401750 by josmiceli(9654) on 2012-08-14 21:11:14 (Show Source):
You can put this solution on YOUR website!Let  = the original number of residents
Let  = the original cost/resident
(1)
(2) 
-------------------------------
(2) 
Substitute (1) into (2)
(2) 
(2) 
(2) 
Substitute this back into (1)
(1)
(1) 
(1)

The revised cost/resident is $131
check:
(1)
(1) 
(1) 
and
(2) 
(2) 
{2) 
------------------------
This is close but a little off. Can you see where I
messed up?
|
Exponents-negative-and-fractional/637367: How do you solve 2^(5/2) - 2^(3/2)? The fractions are fractional exponents (not mixed numbers). I submitted this question yesterday but I apologize it was in the wrong form (I did not include parentheses.)The answer is supposed to be 2^3/2 according to the answer key. I need to see it worked out line by line. Thanks so much! 1 solutions
Answer 401598 by josmiceli(9654) on 2012-08-14 10:35:26 (Show Source):
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Probability-and-statistics/637333: IN HOW MANY WAYS CAN 3 COINS FALL? 1 solutions
Answer 401570 by josmiceli(9654) on 2012-08-14 08:16:04 (Show Source):
You can put this solution on YOUR website!H H H
T T T
H T T
H H T
T H T
H T H
T T H
H H T
--------
This is 8 ways, which is
2*2*2
You multiply because it is
( 2 choices ) AND ( 2 choices ) AND ( 2 choices )
--------
It sounds like the coins are falling all at
once, and the order doesn't matter, so
H T T is the same as T T H or T H T , so
that means the coins can fall in 4 ways
H H H
T T T
H H T
T T H
|
Trigonometry-basics/637336: solution and graph for this
y= 3 + 2 sin (2x - pi/2) 1 solutions
Answer 401569 by josmiceli(9654) on 2012-08-14 08:02:30 (Show Source):
You can put this solution on YOUR website!Here's a chart:
-----------
x . . . . . . 2x . . . . . . 2x - pi/2 . . . . . . 3 + 2sin(2x - pi/2)
pi/2 . . . . pi . . . . . . . pi/2 . . . . . . . . . . 4
pi . . . . . . 2pi . . . . . . 3pi/2 . . . . . . . . . . 1
3pi/2 . . . 3pi . . . . . . 5pi/2 . . . . . . . . . . 4
-----------------------------------
It looks like y has a max of 
and a min of  , and every pi/2
y is 1 or 4.
here's the plot:
|
Graphs/637114: I am studying for the GRE and have a question about f(x) equations. The problem is f(x) = 3x + 4. I haven't studied f(x) problems in quite a while. How do I figure out what the slope of f is, and what the x and y-intercepts of f is? Also, any other information about slope equations would be greatly appreciated. Thank you! 1 solutions
Answer 401431 by josmiceli(9654) on 2012-08-13 14:49:13 (Show Source):
You can put this solution on YOUR website!The definition of slope is ( change in y ) / ( change in x )
You need either 2 points on a curve or the equation
of that curve to find the slope.
When the equation is in the form  ,
 is the slope, so if the equation is
 , the slope is 
-------------
Note that  , and you can use either definition.
|
Travel_Word_Problems/637048: a plane traveled 1386 miles to singapore and back. The trip there was with the wind. It took 9 hours. The trip back was into the wind. the trip back took 11 hours. Find the speed of the plane in still air and the speed of the wind. 1 solutions
Answer 401375 by josmiceli(9654) on 2012-08-13 11:00:06 (Show Source):
You can put this solution on YOUR website!Let  = the speed of the wind in mi/hr
Let  = the speed of the plane in still air
 = the plane's speed going with the wind
 = the plane's speed going against the wind
----------------
Equation going with the wind:
(1) 
Equation going against the wind:
(2) 
----------------------
(1) 
(1) 
Substitute this result into (2)
(2) 
(2) 
(2) 
(2) 
(2) 
Substitute this result into (1) or (2)
(2) 
(2) 
(2) 
The plane's speed in still air is 140 mi/hr
The speed of the wind is 14 mi/hr
check:
(1) 
(1) 
(1) 
OK
|
Miscellaneous_Word_Problems/637051: I cannot figure out how this is done: "you need a piece of lumber 5' 11" long. How much will you have left over if you cut what you need from a piece 8' 3" long" 1 solutions
Answer 401371 by josmiceli(9654) on 2012-08-13 10:44:45 (Show Source):
You can put this solution on YOUR website!You need to subtract feet from feet
and inches from inches.
The feet is easy, but how do you subtract
11 inches from 3 inches?
--------------------
What you do is borrow 12 inches from
the 8 feet, so now it looks like
7' 15"
------------------------
Now subtract feet from feet and inches
from inches
7' 15" minus 5' 11" = 2' 4"
|
Polynomials-and-rational-expressions/636899: I'm trying to help a friend who is in a course segment called "real zeros of a polynomial function". The math is OK, but we're stymied by the vagueness of the problem wording.
One portion of a problem boils down to "express 1/(3x^6 + 86x^3 + 135) as a QUOTIENT".
Well, it is a quotient already. And it can't be neatly simplified or factored. What are they asking for? 1 solutions
Answer 401277 by josmiceli(9654) on 2012-08-12 18:08:24 (Show Source):
You can put this solution on YOUR website!All I can figure is that somehow they want you to
find the value of  , then plug it into the
denominator, and come up with a decimal
number for the fraction.
|
Miscellaneous_Word_Problems/636903: Jimmy is having speaker wire run in his family room. To install the speaker wire, one company charges $85 plus $0.20 per foot of wire used. If Jimmy needs the cost of installation to remain below $95, how many feet of wire can he have installed?
1 solutions
Answer 401276 by josmiceli(9654) on 2012-08-12 18:00:13 (Show Source):
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Expressions-with-variables/636896: Use the equations below to find the length of the pipe.
(there is a pipe separated into an a, b, and c section)
a + b = 15
b - a = 3
a + b - 12 = c
How do i set up an equation for this problem?
Thanks! 1 solutions
Answer 401274 by josmiceli(9654) on 2012-08-12 17:54:26 (Show Source):
You can put this solution on YOUR website!There are 3 equations and 3 unknowns.
That means this is solvable, since
number of unknowns must equal
number of equations to solve.
------------
(1)
(2)
(3) 
------------------
(1) 
Substitute this into (2)
(2) 
(2) 
(2) 
(2) 
(2) 
and, since
(1) 
(1) 
(1) 
Substitute these results into (3)
(3) 
(3) 
(3) 
(3) 
-----------
|
Rate-of-work-word-problems/636702: A, B, and C can do a piece of work in 10 days. A and B can do it in 12 days, A and C in 20 days. How many days would it take each to do the work alone? 1 solutions
Answer 401180 by josmiceli(9654) on 2012-08-12 02:18:49 (Show Source):
You can put this solution on YOUR website!Let their rates of working in ( fraction of work finished ) / ( days to do it )
=  ,  , and 
given:
(1) 
(2) 
(3) 
-----------------------
(2) 
(3) 
and, by substitution,
(1) 
(1) 
(1) 
{1) 
(1) 
-----------------
(2) 
(2) 
(2) 
(2) 
----------------
(3) 
(3) 
(3) 
(3) 
-----------------
A takes 30 days working alone
B takes 20 days working alone
C takes 60 days working alone
------------------------
check:
(1) 
(1) 
(1) 
(1) 
OK
|
Graphs/636699: I would appreciate your help on this: f(x)=-2x^2+2x+6. Find the vertex, the line of symmetry, the maximum or minimum value of the quadratic function, and graph the function.
This is what I have so far.
x coordinate of the vertex is 1/2
the y-coordinate of the vertex is_____
the equation of the line of symmetry is x=
The maximum /minimum of f(x)is_____
The value f(1/2)=13/2 is maximum 1 solutions
Answer 401179 by josmiceli(9654) on 2012-08-12 01:45:31 (Show Source):
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Quadratic_Equations/636499: f(x)=x2 + 2x - 9
determine whether the given quadratic function has a minmum or maximun value. then find the coordinated of the mininmun or maximun point. 1 solutions
Answer 401058 by josmiceli(9654) on 2012-08-11 08:04:34 (Show Source):
You can put this solution on YOUR website!
Since the coefficient of the squared term is positive
( +1 ), then the function has a minimum.
-------------
The  value of the minimum will
be at  when the
equation is in the form

-----------------
Plug this back into the equation

------------
So the minimum is at (-1,-10)
Here's a plot:
|
logarithm/635521: Find all of the solutions to the equation:
Could you please guide me through this?
Thank you so much for helping and thank you so much for your time in helping me with this problem! 1 solutions
Answer 400387 by josmiceli(9654) on 2012-08-07 17:27:08 (Show Source):
You can put this solution on YOUR website!

---------------------
The sine is negative in the 3rd and 4th
quadrants. In the 3rd quadrant, the
angle is  radians or
 degrees
----------------
In the 4th quadrant, the angle is
 radians, or
 degrees
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Travel_Word_Problems/635016: Karen traveled 640 miles by boat and returned by plane. She spent 42 hours traveling on the trip. If the plane is 20 times faster than the rate of the boat, find each rate. 1 solutions
Answer 400044 by josmiceli(9654) on 2012-08-05 20:35:09 (Show Source):
You can put this solution on YOUR website!Let  = time spent traveling by boat
 = time spent traveling by plane
Let  = rate by boat
Let  = rate by plane
------------------------
Equation for boat:
(1) 
(2) 
-----------------------
(2) 
Substitute (1) into (2)
(2) 
(2) 
------------------
You can finish. Find 
and
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