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Miscellaneous_Word_Problems/374771: At 6h00 a clock strikes the bell 6 times. The time between first and last strike is 30 seconds. How long does it take to strike the bell at 12h00 ?
1 solutions

Answer 266526 by rfer(12644) About Me  on 2010-11-22 00:34:39 (Show Source):


Numeric_Fractions/374766: simplify each expression 3/4 divided by 6/5+8/12 times 6/9 -5/12
1 solutions

Answer 266525 by rfer(12644) About Me  on 2010-11-22 00:33:02 (Show Source):
You can put this solution on YOUR website!
3/4*5/6+8/12*6/9-5/12
15/24+48/108-5/12
5/8+4/9-5/12
45/72+32/72-30/72=47/72


Numeric_Fractions/374777: reduce to the lowest term.. (-6/7)divided by (5/7)(-5/6)
1 solutions

Answer 266523 by rfer(12644) About Me  on 2010-11-22 00:27:07 (Show Source):
You can put this solution on YOUR website!
-6/7*7/5*-5/6=210/210=1


Average/374696: What is the slope of the line described by -6x = -2y + 5?
1 solutions

Answer 266482 by rfer(12644) About Me  on 2010-11-21 21:08:31 (Show Source):
You can put this solution on YOUR website!
2y=6x+5
y=3x+2.5
slope m=3


Percentage-and-ratio-word-problems/374681: how do you solve this? --> a jacket costs $120 which includes a 5% sales tax. what was the cost of the jacket without the tax?
1 solutions

Answer 266481 by rfer(12644) About Me  on 2010-11-21 21:07:00 (Show Source):
You can put this solution on YOUR website!
120/1.05=114.29


percentage/374624: The population of a city is 350,600. If 0.1% of the population
earns more than $200,000, about how many people are in this category?

1 solutions

Answer 266473 by rfer(12644) About Me  on 2010-11-21 20:06:28 (Show Source):
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350000*0.001=350


expressions/374646: Evaluate -6 + x ÷ 4(8 – x^2) for x = -4. Please show all of your work
1 solutions

Answer 266472 by rfer(12644) About Me  on 2010-11-21 20:03:41 (Show Source):
You can put this solution on YOUR website!
-6+-4/4(8--4^2)
-6+-4/-8
-6+.5
-5.5


Divisibility_and_Prime_Numbers/374642: A CD player is on sale for $270. What was the original price of the CD player if the discount was 2/5 of the original price?
1 solutions

Answer 266469 by rfer(12644) About Me  on 2010-11-21 20:00:15 (Show Source):
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270/.060=$450


Expressions-with-variables/374508: 4.2z=-4(0.6z-1.2)
1 solutions

Answer 266427 by rfer(12644) About Me  on 2010-11-21 18:09:34 (Show Source):
You can put this solution on YOUR website!
4.2z=-2.4z+4.8
add 2.4z to both sides
6.6z=4.8
divide by 6.6
z=(4.8)/(6.6)
z=0.073


Linear-equations/374544: Write the standard form of the equation of each line given the slope and y-intercept:
Slope=9, y intercept=4
The answer is 9x-y=-4 but how?
1 solutions

Answer 266426 by rfer(12644) About Me  on 2010-11-21 18:05:48 (Show Source):
You can put this solution on YOUR website!
slope intcept form
y=mx+b
y=9x+4
change to standard form
-9x+y=4
multiply through by -1
9x-y=-4


Matrices-and-determiminant/374563: what is the determinante
2x+3y=4
x-2y=9
1 solutions

Answer 266425 by rfer(12644) About Me  on 2010-11-21 18:01:58 (Show Source):
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a=2 b=3 c-4
a=1 b=2 c=9


Linear-equations/374556: Write the standard form of the equation of each line:
y=-7/5x+1 answer is 7x+5y=5 but how?
y+4=-7(x-1) answer is 7x+y=3 how?
-10x-y=-5 answer is 10x+y=5 how?
y=3/2x+5 answer is 3x-2y=10 how?

1 solutions

Answer 266424 by rfer(12644) About Me  on 2010-11-21 17:59:48 (Show Source):
You can put this solution on YOUR website!
y=-7/5x+1
multiply both sides by 5
5y=-7x+5
add 7x to both sides
7x+5y=5
--------------------
y+4=-7(x-1)
multiply
y+4=-7x+7
add 7x to both sides
7x+y+4=7
subtract 4 from both sides
7x+y=3
---------------------
-10x-y=-5
multiply through by -1
10x+y=5
---------------------------
You try the last one.
Bob


Trigonometry-basics/374557: Please help me solve this question sin degree 32?
1 solutions

Answer 266423 by rfer(12644) About Me  on 2010-11-21 17:51:37 (Show Source):


Linear-systems/374204: Solve the following equation for y
8/y+2=-3
1 solutions

Answer 266308 by rfer(12644) About Me  on 2010-11-20 22:20:51 (Show Source):
You can put this solution on YOUR website!
8/y=-5
8=-5y
y=-1.6


Inverses/374163: Perform the indicated operation and, if possible, simplify. Please show all of your work
(-5/7-2/5)
1 solutions

Answer 266306 by rfer(12644) About Me  on 2010-11-20 22:18:39 (Show Source):
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-25/35-14/35=-39/35=-1 4/35


Geometry_proofs/374148: What is the point of geometry proofs?
1 solutions

Answer 266271 by rfer(12644) About Me  on 2010-11-20 20:31:55 (Show Source):
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To learn an orderly method of understanding what is taking place.


Radicals/374153: how do I begain to find the distance between each pair of points.
(-5,-2) and (-7,-1)
1 solutions

Answer 266270 by rfer(12644) About Me  on 2010-11-20 20:30:10 (Show Source):
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you use a form of the Pythagorem therom
d=sqrt((-7--5)^2+(-1--2)^2)
d=sqrt((-2)^2+(1)^2)
d=sqrt(4+1)
d=2.236


test/374137: If you know the mean is 6 and the sum of the scores is 48. What is n?

1 solutions

Answer 266239 by rfer(12644) About Me  on 2010-11-20 18:53:39 (Show Source):


Proportions/374095: Maria earns $603.75 for 35 hours of work. What is her rate of pay per hour.
1 solutions

Answer 266231 by rfer(12644) About Me  on 2010-11-20 17:47:38 (Show Source):
You can put this solution on YOUR website!
603.75/35=17.25 per hr


Finance/374017: Larry has $2600 to invest and needs $3100 in 13 years. What annual rate of return will he need to get in order to accomplish his goal, if interest is compounded continuously? (Round your answer to two decimals.)
a.1.35%
b.3.44%
c.1.44%
d.2.44%''.

1 solutions

Answer 266186 by rfer(12644) About Me  on 2010-11-20 13:17:06 (Show Source):
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A) 1.35%
A=P(e)^rt
A=2600(2.7183)^r(13)


Rational-functions/373994: 100 invested at 7% compounded quartely after a period of 2 years?
1 solutions

Answer 266184 by rfer(12644) About Me  on 2010-11-20 13:04:04 (Show Source):
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A=100(1+0.07/4)^4*2
A=100(1.0175)^8
A=100*1.14888
A=114.89


Complex_Numbers/374008: I know the answer is 25, but im unsure if it's negative or positive.
(-5i)^2
the i is the imaginary number, not a variable.
1 solutions

Answer 266183 by rfer(12644) About Me  on 2010-11-20 13:00:25 (Show Source):
You can put this solution on YOUR website!
It has been awhile but I think i =-1
so -5*-1=+5^2=+25


real-numbers/373771: how do i multiply more than two real numbers? For example
-12(-3)(-7)(-5/21) =

1 solutions

Answer 265987 by rfer(12644) About Me  on 2010-11-19 16:23:21 (Show Source):
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1260/5=252
even number of minus signs = a plus answer


Polynomials-and-rational-expressions/373772: Describe the steps involved, in detail, in finding the product of x+2 and x-2?
1 solutions

Answer 265985 by rfer(12644) About Me  on 2010-11-19 16:20:42 (Show Source):
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(x+2)(x-2)
x^2-2x+2x-4
combine
x^2-4


percentage/373768: How do you turn a number or fraction into a percentage?
1 solutions

Answer 265984 by rfer(12644) About Me  on 2010-11-19 16:19:22 (Show Source):
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whole number 2 move decimal two places right 200%
fraction 1/4= 0.25= 25%
decimail 0.75=75%


Linear-equations/373540: how dou you solve the linear system by graphing?
y=-x+3
y=x+1
1 solutions

Answer 265852 by rfer(12644) About Me  on 2010-11-19 01:15:38 (Show Source):
You can put this solution on YOUR website!
y=-x+3
y=x+1
----------
-x+3=x+1
-2x=-2
x=1
--------------
y=-1+3
y=2
----------------
2=1+1


Linear_Algebra/373535: Hello,
I need help solving this problem, thanks in advance.
f(x) = $35.99 * 7 days

1 solutions

Answer 265851 by rfer(12644) About Me  on 2010-11-19 01:12:24 (Show Source):
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f(7)=35.99*7
f(7)=251.93


percentage/373544: steps on how to find the final price of each item
when you have this problem
dress:$70.00
Discount:30%
tax:7%
1 solutions

Answer 265850 by rfer(12644) About Me  on 2010-11-19 01:10:19 (Show Source):
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70*.70=49
49*1.07=52.43


Miscellaneous_Word_Problems/373557: Charlie drove 250 miles using 9 gallons of gas. At this rate, how many gallons of gas would he need to drive 350 miles?
1 solutions

Answer 265849 by rfer(12644) About Me  on 2010-11-19 01:07:37 (Show Source):
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9/250=x/350
250x=3150
x=12.6 gal


Number-Line/373450: 1. For homework we had to make number lines out of the problems. i Know how to do this type of problem: x+3>9 the answer is: x>6
what i dont get is this type of problem: 2x+6<14
1 solutions

Answer 265798 by rfer(12644) About Me  on 2010-11-18 21:01:23 (Show Source):
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2x+6 < 14
2x < 8
now divide both sides by 2
x < 4
Just one additional step.


test/373449: Roberto built a model racecar that is 3 inches long and has a scale of 0.5inches = 2 feet. he determined that the real car must be 3•2 or 6 feet long. is this correct? explain
1 solutions

Answer 265797 by rfer(12644) About Me  on 2010-11-18 20:58:16 (Show Source):
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3/.5=6
6*2=12 ft
6 half inch pieces in 3 inches