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rwm answered: 913 problems
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Numbers_Word_Problems/449874: the greatest of three numbers equals the product of -7 and the smallest number, and the remaining number is 18 more than the smallest. find three numbers if the greatest is 3 less than twice the sum of the other two numbers
1 solutions
Answer 309427 by rwm(914)   on 2011-05-15 22:39:05 (Show Source):
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Permutations/449851: Prestige Builders has a development of new homes.There are five different floor plans,four exterior colors,and an option of either one-car or two -car garage.How many choices are there for one home ?
1 solutions
Answer 309418 by rwm(914) on 2011-05-15 22:26:18 (Show Source):
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test/449849: Dave can paint a room in one hour less time than Rachael. Together they can do it in five hours. How long will it take Dave if he does the job alone?
1 solutions
Answer 309413 by rwm(914) on 2011-05-15 22:04:12 (Show Source):
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Quadratic-relations-and-conic-sections/449853: please help me. I have trouble completing the square to find the center & radius. The problem is:
x^2+y^2+2x+10y+25=0 ;
I need the answer & I need to know how to do more of those problems, thanks.
1 solutions
Answer 309410 by rwm(914) on 2011-05-15 21:53:55 (Show Source):
You can put this solution on YOUR website!Separate x's and y's and constants
This is a circle.
x^2+2x+(y+5)^2 = 0
(x+1)^2+(y+5)^2 = 1
center -1,-5
radius 1
area =pi
perimeter (circumference) =2pi
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Rational-functions/449838: When it comes to solving Rational Functions, I get lost when I have a Sum and Product Problem on both sides of the equals sign, or when I get have to multiply to get numbers like x^2. On my worksheet for homework, this problem is specifically giving me trouble.
(x/x-3)+(x-1/x^2-9)=(2x-3/x+3)
I've tried multiplying both sides by (x+3)(x-3), but i screw up everytime. Thanks for your help.
1 solutions
Answer 309407 by rwm(914) on 2011-05-15 21:47:18 (Show Source):
You can put this solution on YOUR website!I assume the problem is really
(x)/(x-3)+(x-1)/(x^2-9)=(2x-3)/(x+3)
You don't want to multiply by (x+3)(x-3) which is (x^2-9)
You want to get the same denominator of (x^2-9)
so sometimes you will multiply by (x+3)/(x+3) which is 1/1
and sometimes by (x-3)/(x-3) which is also 1/1
We must discount any solutions where x=3 or -3
since they would lead to a zero denominator.
it ends up
(x^2+4 x-1)/((x-3) (x+3)) = (2 x-3)/(x+3)
((x-13) x+10)/(x^2-9) = 0
4/129 (x-13/2)^2 = 1
x = 1/2 (13-sqrt(129))
x = 1/2 (13+sqrt(129))
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Rate-of-work-word-problems/441932: a painter bought 12 gallons of paint to paint two rooms. one room is twice the size of the other and requires 3 coats of paint. the smaller room requires only 2 coats. the client decided not to paint the second room after all. how many gallons of paint will the painter have to return?
1 solutions
Answer 309280 by rwm(914) on 2011-05-15 13:32:01 (Show Source):
You can put this solution on YOUR website!No idea because we aren't told how much paint is needed for one room nor the other nor both together. WE are only told how much paint the painter bought.
We are not told the relationship between amount bought and the amount needed.
Assuming that 12 gallons was the exact amount needed for the two rooms
we can say that
room one is 2x and needs 6x paint for 3 coats
room two is x and uses 2x paint for 2 coats
6x+2x=8x
8x=12
x=12/8=3/2
so room one needs 9 gallons
and room two needs 3 gallons
assuming that the room not painted is the smaller room (we are not told which room is the non painted room) the 3 gallons are returned.
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Rate-of-work-word-problems/443501: it takes x hours to fill a swimming pool when only hose 1 is used. It takes y hours to fill the pool if only hose 2 is used. Write a rational expression to show how long How takes to fill the pool if both hoses are used. Can you explain the answer and how you got to it?
1 solutions
Answer 309276 by rwm(914) on 2011-05-15 13:23:42 (Show Source):
You can put this solution on YOUR website!z/x+z/y=1
z is the time together
x is the time for one hose
y is the time for hose two
1 is the whole job
hose one does 1/x per hour
hose two does 1/y per hour
the whole job takes z hours
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Rate-of-work-word-problems/444102: Jane can paint a 12 foot by 12 foot wall in 3/4 of an hour. How long will it take her to paint another wall that is 15 x 16 ft. Do not use cross multiplication.Draw a picture.
1 solutions
Answer 309275 by rwm(914) on 2011-05-15 13:20:27 (Show Source):
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Rate-of-work-word-problems/444113: Jean paints a house in 4 days. Brett can paint the same house in 6 days and Joe can paint the same house in 2 days. How much time will it take to paint the house together?
1 solutions
Answer 309273 by rwm(914) on 2011-05-15 13:12:00 (Show Source):
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Evaluation_Word_Problems/444324: Jim has 5 pieces of string. He needs to choose the piece that will be able to go around his 36-inch waist. His belt broke, and his pants are falling down. The piece needs to be at least 4 inches longer than his waist so he can tie a knot in it, but it cannot be more that 6 inches longer so that the ends will not show from under his shirt. Which of the following pieces of string will work the best?
A= 3feet
B= 3 3/4 feet
C= 3 1/2 feet
D= 3 1/4 feet
E= 2 1/2 feet
1 solutions
Answer 309271 by rwm(914) on 2011-05-15 13:09:00 (Show Source):
You can put this solution on YOUR website!right away we can eliminate a and e as being too short.
1/4 foot is 3 inches too short
3/4 foot is 9 inches too long
which leaves 3 1/2 foot which is 6 inches which is not more than 6 inches
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Rate-of-work-word-problems/444755: an experienced painter can paint a garage twice as fast as his apprentice. working together, the painters require 4 hours to paint a garage. how long would it take the experienced painter working alone to paint the garage?
1 solutions
Answer 309269 by rwm(914) on 2011-05-15 13:03:58 (Show Source):
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Travel_Word_Problems/449091: A helicopter hovering at 800 feet drps relief supplies to the ground. How long will it take the supplies to hit the ground? Round to the nearest second.
1 solutions
Answer 309264 by rwm(914) on 2011-05-15 12:52:34 (Show Source):
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Rate-of-work-word-problems/449543: A small water pipe takes twice as long to fill a tank as does a larger water pipe. With both pipes open, it takes 16 h to fill the tank. Find the time it would take the small pipe working alone to fill the tank.
1 solutions
Answer 309263 by rwm(914) on 2011-05-15 12:50:46 (Show Source):
You can put this solution on YOUR website!16/x+16/2x=1
16/x+8/x=1
24/x=1
x=24 hrs for the larger pipe.
2x=48 hrs for the smaller pipe
check
16/24+16/48=1
4/6+1/3=1
2/3+1/3=1
ok
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Rate-of-work-word-problems/447225: PROBLEM 16
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It takes Daniel ten hours to oil the lanes in a bowling alley. Ndiba can oil the same lanes in 9 hours. If they worked together how long would it take them?
1 solutions
Answer 309260 by rwm(914) on 2011-05-15 12:44:50 (Show Source):
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Rate-of-work-word-problems/449552: Gina and Cal can spray an orchard in 8 hours. Gina working alone would take 12 hours to do the job. How long would it take Cal working alone to do the job?
1 solutions
Answer 309259 by rwm(914) on 2011-05-15 12:41:07 (Show Source):
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Rational-functions/449579: If the length of a rectangle is represented by x+6 and the width is represented by x. What is a rational function, R, to represent the ratio of the area, A, of the rectangle to its perimeter, P?
1 solutions
Answer 309257 by rwm(914) on 2011-05-15 12:36:10 (Show Source):
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Expressions-with-variables/449570: Please help! I have this story problem:
In 1991, the life expectancy for males in a certain country is 66.4 years. In 1996, it was 70.0 years. "E" is to represent the life expectancy in year t and t represents the number of years since 1991.
E=__(t) + __
(round to the nearest tenth)
Use the function to predict the life expectancy of males in 2009.
E(18)=__
(round to the nearest tenth)
1 solutions
Answer 309256 by rwm(914) on 2011-05-15 12:34:35 (Show Source):
You can put this solution on YOUR website!Think of (66.4, 1991 or 0) and (70.0, 1996 or 5) as points on the line. find the equation of the line for those two points.
and plug in 2009 or 18 for y in the equation and find x
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Equations/449558: Alex cuts a 36 inch piece of wire into 2 pieces. Each piece will be bent into a square. The area of the larger square will be four times the area of the smaller square. What will be the area of the smaller square?
1 solutions
Answer 309253 by rwm(914) on 2011-05-15 12:30:06 (Show Source):
You can put this solution on YOUR website!a/4*a/4=4*(b/4*b/4)
a^2/16=b^2/4
4a^2=16b^2
a^2=4b^2
a=2b
a=-2b
we reject any solutions that are negative.
a+b=36
2b+b=36
3b=36
b=12
a=36-b
a=24
a=24 b=12
each side of the 24 inch wire will be 6 inches
6*6=36 in^2
each side of the 12 in wire will be 3 inches
3*3=9 in^2
check
36 is 4 times 9
ok
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Length-and-distance/449575: If a car starts from A towards B with some velocity. Due to some problem in the engine after traveling 30km, the car goes with 4/5 th of its actual velocity
The car reaches B 45 min later to the actual time. If the car engine fails after traveling 45km, the car reaches the destination B 36min late to the actual time What is the initial velocity of car and what is the distance between A and B in km
1 solutions
Answer 309250 by rwm(914) on 2011-05-15 12:18:13 (Show Source):
You can put this solution on YOUR website!Actual time is what the time really was. So your talk about actual time makes no sense. Perhaps you mean to say scheduled or planned time.
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Travel_Word_Problems/449567: A runner covers 31km in 4 hours. He cycled part of the way at 14 km/h and he walked the rest of the way at 4 km/h. How far did he walk?
1 solutions
Answer 309246 by rwm(914) on 2011-05-15 12:07:40 (Show Source):
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Equations/449565: I have problem solving with fractions . Solve using the multiplication principle.
is this right if not can you example.
-8x >1/15
(8/-8>(1/ 15) *(1/(-8)) X > - 1/15*1/8 >1/19
1 solutions
Answer 309244 by rwm(914) on 2011-05-15 11:55:40 (Show Source):
You can put this solution on YOUR website!I have no idea what you are doing.
It just looks like you threw some numbers together for no particular reason.
-8x> 1/15
divide by -8 on both sides and switch the sign
x< 1/15/-8
x< -1/(8*15)
x<-1/120
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Equations/449177: B spends 3/8 of his pocket money.If he has $5.20 left, how much did he have to begin with?
1 solutions
Answer 309035 by rwm(914) on 2011-05-14 06:33:19 (Show Source):
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Evaluation_Word_Problems/449113: Identify the equation of direct variation given that y varies directly with x.
x is 84 when y is 6.
answers:
a) y = 14x
b) y = 84x
c) y = 1/14x
d) y = 1/48x
1 solutions
Answer 309008 by rwm(914) on 2011-05-13 21:39:27 (Show Source):
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