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Rectangles/275354: the perimeter of a rectangle is 180 centimeters. The ratio of the length to the width is 7:3. Find the width of the rectangle
1 solutions

Answer 200898 by rfer(12675) About Me  on 2010-02-28 21:57:58 (Show Source):
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2(7x)+2(3x)=180
14x+6x=180
20x=180
x=9
7x=63
3x=27


Graphs/275367: You are choosing from from two plans at a discount warehouse. Plan A offers an annual membership fee of $300 and you pay 70% or the manufacturers recommended list price. Plan B offers an annual membership price of $40 and you pay 90% of the manufacturers recommended list price. How many dollars of merchandise would you have to purchase in a year to pay the same amount under both plans? What is the cost for both plans?
1 solutions

Answer 200896 by rfer(12675) About Me  on 2010-02-28 21:52:10 (Show Source):
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300+.7x=40+.9x
240=.2x
x=$1200


Probability-and-statistics/275386: In a homicide case 3 different witnesses picked the same man from a line up. The line up contained 5 men. If the identifications were made by random guesses, find the probability that all 3 witnesses would pick the same person.
1 solutions

Answer 200894 by rfer(12675) About Me  on 2010-02-28 21:45:58 (Show Source):
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1/5*1/5*1/5=1/125


Money_Word_Problems/275395: Steven paid $119.84 for a nw jacket. This included 7% sales tax. What was the cost of the jacket before taxes.
1 solutions

Answer 200891 by rfer(12675) About Me  on 2010-02-28 21:43:54 (Show Source):
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119.84/1.07=$112


Linear-equations/275422: find the slope of the line passing through the points (7,0) and (0,10)
1 solutions

Answer 200890 by rfer(12675) About Me  on 2010-02-28 21:40:15 (Show Source):
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-10/7
or -1 3/7


Triangles/275402: In a triangle ABC, angle B is 4 times angle A, angle C is 2 degrees less than 5 times angle A.Find the size of the angles
1 solutions

Answer 200887 by rfer(12675) About Me  on 2010-02-28 21:36:11 (Show Source):
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a=x
b=4x
c=5x-2
x+4x+5x-2=180
10x=182
x=18.2 degrees
4x=72.8 degrees
5x-2=89 degrees


Evaluation_Word_Problems/275421: Please help me solve: From a point on a straight road, John and Fred ride bicycles in the Same Direction. John rides 7 miles per hour and Fred rides 13 miles per hour. In how many hours will they be 60 miles apart?

** I know how to do it if they were going different directions but not sure of this problem since they are going SAME direction.
1 solutions

Answer 200886 by rfer(12675) About Me  on 2010-02-28 21:32:10 (Show Source):
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they are moving apart at 6 mph
60/6=10 hrs


Numeric_Fractions/275403: What percent of 24 is 15?
1 solutions

Answer 200885 by rfer(12675) About Me  on 2010-02-28 21:30:40 (Show Source):
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15/24=.625=62.5%


Travel_Word_Problems/275416: 2 cars leave town at the same time, going the same direction. ONe is traveling 40 mph, and the other is going 65 mph. In how many hours will they be 75 miles apart?
I have erased my work several times, so I don't know what I have or had anymore.
1 solutions

Answer 200882 by rfer(12675) About Me  on 2010-02-28 21:27:37 (Show Source):
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moving apart at 25 mph
75/25=3 hrs


Systems-of-equations/274725: Please Help me solve this problem.
How do you solve 6y-x=-36
y=-3x?
Using subsitution.
1 solutions

Answer 200467 by rfer(12675) About Me  on 2010-02-26 20:09:31 (Show Source):
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6(-3x)-x=-36
-18x-x=-36
-19x=-36
x=1.9
------------
6y-1.89=-36
6y=34.2
y=5.7
-------------
5.7=-3(1.9)


Volume/274664: I have a tank that is 7 feet at it's greatest width and 7 feet high. It has a bottom and no top. What is the area square footage of the tank so that I can paint a liner inside it? Thank you.
1 solutions

Answer 200463 by rfer(12675) About Me  on 2010-02-26 19:51:22 (Show Source):
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not enough information


Numbers_Word_Problems/274674: Two positive numbers have a difference of 5. The larger number is 1 more than twice the smaller. Find the two number.
1 solutions

Answer 200461 by rfer(12675) About Me  on 2010-02-26 19:45:28 (Show Source):
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x-2x+1=5
x+1=5
x=4
2x+1=9


Polynomials-and-rational-expressions/274641: A rectangular piece of land, bounded on one side by a river, is to be fenced on the other three sides. What is the larges possible area that can be enclosed by 300 metres of fencing?
1 solutions

Answer 200459 by rfer(12675) About Me  on 2010-02-26 19:42:16 (Show Source):
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100*100=10,000 sq m


Pythagorean-theorem/274727: Find the measure of the diagonal of one face of a cube whose side measures 12 cm.

1 solutions

Answer 200455 by rfer(12675) About Me  on 2010-02-26 19:37:52 (Show Source):
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12^2+12^2=c^2
144+144=288
sq rt of 288=17cm


Numbers_Word_Problems/274679: One number is 5 more than 4 times another. Their sum is 35. Find the 2 numbers.
1 solutions

Answer 200454 by rfer(12675) About Me  on 2010-02-26 19:36:04 (Show Source):
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x+4x+5=35
5x=30
x=6
4x+5=29


Triangles/274691: Angles of a triangle. The second angle of a triangular
building lot is three times as large as the first. The
third angle is 10 degrees more than the sum of the other two
angles. Find the measure of the third angle.
1 solutions

Answer 200451 by rfer(12675) About Me  on 2010-02-26 19:28:39 (Show Source):
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x+3x+(x+3x+10)=180
8x+10=180
8x=170
x=21.25 degrees
3x=63.75 degrees
x+3x+10=95 degrees


Travel_Word_Problems/272919: Jack runs the mile in 3 minutes and 56.7 seconds. How long does it take him to run 2km at the same average speed? PLEASE SHOW HOW TO DO IT
1 solutions

Answer 199464 by rfer(12675) About Me  on 2010-02-22 17:10:40 (Show Source):
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one mile equals 1.61 km
3*60+56.7=236.7 sec for 1.61 km
236.7/1.61=147 sec per km
147*2=294 sec for 2 km or 4 min 54 sec


Linear-equations/272607: find the slope of the line that passes through the points (-9,2) and (1,1). Reduce your answer.

1 solutions

Answer 199358 by rfer(12675) About Me  on 2010-02-21 22:30:39 (Show Source):


Inequalities/272605: I am not sure how to do this problem:
1/2+2/3=x/6 do i find the lcd and multiply that by the top?
1 solutions

Answer 199357 by rfer(12675) About Me  on 2010-02-21 22:28:00 (Show Source):
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1/2+2/3=x/6
3/6+4/6=x/6
7/6=x/6
6/1*7/6=x
42/6=x
7=x


Exponents-negative-and-fractional/272546: -(-9+8y)
Find an equivalent expression without parentheses.
1 solutions

Answer 199354 by rfer(12675) About Me  on 2010-02-21 22:19:48 (Show Source):


Rectangles/272555: is 100 inches greater than 3 yards

1 solutions

Answer 199353 by rfer(12675) About Me  on 2010-02-21 22:16:54 (Show Source):


Numeric_Fractions/272569: 1/2 + (2/3 / 3/4) - (4/5*5/6)=?
1 solutions

Answer 199352 by rfer(12675) About Me  on 2010-02-21 22:14:34 (Show Source):
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1/2+(2/3/3/4)-(4/5*5/6)=
1/2+(2/3*4/3)-20/30=
1/2+8/9-20/30=
45/90+80/90-60/90=65/90=13/18


percentage/272601: how do you find simple intrest when the percentage is a whole number and then a decimal like 8.5
1 solutions

Answer 199347 by rfer(12675) About Me  on 2010-02-21 22:08:08 (Show Source):
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To change to a decimal move the decimal two places to the left.
8.5% becomes 0.085


Permutations/272057: The probability of rain in a certain city is 1/8 on a given day. Find the probability that rain will fall on exactly one day of a three day visit.
1 solutions

Answer 199159 by rfer(12675) About Me  on 2010-02-20 21:34:39 (Show Source):
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1/8*1/8*1/8=1/512


Linear-systems/272069: 50% of what number is 45
1 solutions

Answer 199158 by rfer(12675) About Me  on 2010-02-20 21:30:29 (Show Source):


Linear-equations/272100: A right angle has one 37 degree angle - find the other two angles?
The smallest angle in a triangle is 1/5 as large as the largest angle. The third angle is twice the smallest angle - find the three angles?
Thank you.
1 solutions

Answer 199157 by rfer(12675) About Me  on 2010-02-20 21:28:36 (Show Source):
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A)
37, 53, 90 degrees
B)
.2x+2(.2x)+x=180
.2x+.4x+x=180
1.6x=180
x=112.5 degrees
.2x=22.5 degrees
2(.2x)=45 degrees


percentage/272132: Last year the population of the town where jared lives increased from 21,900 to 22,020. Using a calculator he computed the percent increase to the nearest whole percent to be 5%. What is his estimation?
1 solutions

Answer 199156 by rfer(12675) About Me  on 2010-02-20 21:22:46 (Show Source):
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the increase is 0.5%
he is very far off


Linear-equations/272103: Give the slope of the line that passes through the points (-5,-2) and (-6,-3) (put in simplest form)
1 solutions

Answer 199155 by rfer(12675) About Me  on 2010-02-20 21:19:28 (Show Source):
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slope = 1
y=mx+b
y=x+3


Linear-systems/272110: the perimeter of a rectangle is 114 feet. it's length is three more than twice its width. find the dimensions of the rectangle
please show the work
1 solutions

Answer 199154 by rfer(12675) About Me  on 2010-02-20 21:16:25 (Show Source):
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x+2x+3=114
3x=111
x=37 ft
2x+3=77 ft


Money_Word_Problems/272131: FINANCE SUPPOSE THAT 7900 IS INVESTED AT 4.1% ANNUAL INTEREST RATE, COMPOUNDED MONTHLY. HOW MUCH MONEY WILL BE IN THE ACCOUNT IN A)11 MONTHS? B)18YRS?
1 solutions

Answer 199153 by rfer(12675) About Me  on 2010-02-20 21:12:49 (Show Source):
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A=P(1+r/n)^nt
A=7900(1+.041/12)^11*.92
A=7900(1.00342)^10.12
A=7900(1.0352)
A=$8178.00
----------------
A=7900(1.00342)^216
A=7900(2.09)
A=$16,511


Pythagorean-theorem/272159: a cube-shaped container has a volume of 3.5L. What is the side length of the container, to the nearest tenth of a centimeter?
1 solutions

Answer 199152 by rfer(12675) About Me  on 2010-02-20 21:00:51 (Show Source):
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sq rt of 3.5=1.5 cm