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Numbers_Word_Problems/426410: Find three consecutive numbers such that the sum of one-fourth the first and one-fifth the second is five less than one-seventh the third.
1 solutions
Answer 296635 by edjones(7569)   on 2011-03-23 22:45:13 (Show Source):
You can put this solution on YOUR website!Let the numbers be x, x+1, x+2.
x/4 + (x+1)/5 = (x+2)/7 - 5
35x+28(x+1)=20(x+2)-700 Multiply each side by 140 (LCM).
35x+28x+28=20x+40-700
43x=-688
x=-16, -15, -14 the three numbers.
.
Ed
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Triangles/426412: one angle of a triangle is a right angle. another angle of the triangle is three times the smallest angle. what are the measures of all the angles?
1 solutions
Answer 296632 by edjones(7569) on 2011-03-23 22:28:18 (Show Source):
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Equations/426437: Solve the equation.
A = pi r^2 for r. Find the radius r of the drum. Round to the nearest tenth.
A = 153.9"^2
1 solutions
Answer 296631 by edjones(7569) on 2011-03-23 22:24:02 (Show Source):
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Probability-and-statistics/426421: In how many different ways 3 people can be selected out of 8 candidates to be awarded with first prize, second prize and third prize (order of selection makes a difference)?
1 solutions
Answer 296623 by edjones(7569) on 2011-03-23 22:12:10 (Show Source):
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Miscellaneous_Word_Problems/426415: Josh and his dad can was the car 40 minutes. Josh can was it by himself in 70 minutes. How long would it take his dad to wash it by himself?
1 solutions
Answer 296618 by edjones(7569) on 2011-03-23 21:53:26 (Show Source):
You can put this solution on YOUR website!1/70 + x = 1/40
4+280x=7 multiply each side by 280.
280x=3
x=3/280 amount of the job his father can do in one minute.
280/3=93 1/3 minutes Length of time it takes father to do the job.
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Ed
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Miscellaneous_Word_Problems/426394: when 25 students went to Washington DC 18 of them visited the Museum of National History and 22 visited the natioonal air and space museum. how many students visited both?
1 solutions
Answer 296609 by edjones(7569) on 2011-03-23 21:24:41 (Show Source):
You can put this solution on YOUR website!Asuming that each student went to at least one of the museums then 15 saw both.
Make a Venn diagram to prove this to yourself.
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Ed
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Square-cubic-other-roots/426347: Write an equation in simplest radical form to express the area, A, of an equilateral triangle in terms of the side x
1 solutions
Answer 296592 by edjones(7569) on 2011-03-23 20:27:32 (Show Source):
You can put this solution on YOUR website!The equilateral triangle contains two 30-60-90 triangles, each with legs of .5x, .5xsqrt(3) and x, the hypotenuse.
The area of one of the 30-60-90 triangles is .5*.5x*.5xsqrt(3)=.125sqrt(3)x^2
the area of the equilateral triangle is .25sqrt(3)x^2
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Ed
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Graphs/426283: I don't know how to do this at all and I understand nothing about inequalities. So If you could maybe email me a link to the BEST and i mean the BEST of the BEST websites that describes that, i would appreciate it SO SO much ! I have to retake my Algebra 1 test and ACE it in order to pass 8th grade. PLEASE I NEED HELP.
1 solutions
Answer 296564 by edjones(7569) on 2011-03-23 19:17:56 (Show Source):
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Proportions/422037: The sum of four numbers is 771. The ratio of the first number to the second number is 2:3. The ratio of the second number to the third number is 5:4. The ratio of the third number to the fourth number is 5:6. What is the second number?
1 solutions
Answer 294621 by edjones(7569) on 2011-03-14 16:22:18 (Show Source):
You can put this solution on YOUR website!Let the 1st number = x
x + 3x/2 + 3x/2 * 4/5 + 6x/5 * 6/5
x + 3x/2 + 6x/5 + 36x/25 = 771
50x+75x+60x+72x=38550 Multiply each side by 50.
257x=38550
x=150
3x/2=225 the 2nd number
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Ed
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Travel_Word_Problems/421874: If Sally can paint a house in 4 hours, and John can paint the same house in 6 hours, how long will it take for both of them to paint the house together?
Thank you
1 solutions
Answer 294513 by edjones(7569) on 2011-03-14 07:51:53 (Show Source):
You can put this solution on YOUR website!Let t=time it takes them working together.
john does 1/6 the job in 1 hr and sally does 1/4.
1/4 + 1/6 = 1/t
3/12 + 2/12 = 5/12
t=12/5 hrs. working together.
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Ed
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Systems-of-equations/421862: Solve for x and y:
(x)^2 / 6 - y / 4 = 1,
x + y = 5
1 solutions
Answer 294511 by edjones(7569) on 2011-03-14 07:46:44 (Show Source):
You can put this solution on YOUR website!(x)^2 / 6 - y / 4 = 1,
x + y = 5
.
y=5-x
x^2/6 - (5-x)/4 = 1
2x^2-3(5-x)=12 Multiply each side by 12.
2x^2+3x-15=12
2x^2+3x-27=0
2*-27=-54; Two factors of -54 whose sum is 3 are 9 and -6
2x^2-6x+9x-27=0
2x(x-3)+9(x-3)=0
(2x+9)(x-3)=0
x=-9/2, y=19/2
x=3, y=2
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Ed
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logarithm/421866: A rectangular block has a square base. The length of each side of the base is (√3 - √2)m and volume of the block is (4√2 - 3√3) cubic metre. Find the height of the block in the form (a√2 + b√3) where a and b are constants.
*√ = square root or under root :)
1 solutions
Answer 294507 by edjones(7569) on 2011-03-14 06:51:05 (Show Source):
You can put this solution on YOUR website!h(sqrt(3)-sqrt(2))^2=4sqrt(2)-3sqrt(3)
h(5-2sqrt(3)(sqrt(2))=...
h=(4sqrt(2)-3sqrt(3))/(5-2sqrt(6))
=(4sqrt(2)-3sqrt(3))/(5-2sqrt(6)) * (5+2sqrt(6))/(5+2sqrt(6)) rationalize the denominator.
=sqrt(3)+2sqrt(2)
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Ed
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Probability-and-statistics/421864: . Application of addition law: Let A be the event that a student is enrolled in an accounting course, and let S be the event that a student is enrolled in a statistics course. It is known that 30% of all students are enrolled in an accounting course and 40% of all students are enrolled in statistics. Included in these numbers are 15% who are enrolled in both statistics and accounting.
a. Find P(S).
b. Find the probability that a student is in accounting and is also in statistics.
c. A student is randomly selected, and it is found that the student is enrolled in accounting. What is the probability that this student is also enrolled in statistics?
d. A student is randomly selected, and it is found that the student is enrolled in statistics. What is the probability that this student is also enrolled in accounting?
e. A student is randomly selected, what is the probability that the student is enrolled in either accounting or statistics or both?
f. From this information, what can be concluded about two events?
1 solutions
Answer 294504 by edjones(7569) on 2011-03-14 06:22:31 (Show Source):
You can put this solution on YOUR website!Make a Venn diagram to understand this problem.
a) .4
b) .15/.30 = .5
c) .5
d) .15/.40 = .375
e) .15+.15+.25=.55
f) They are dependent because P(A|S) <> P(A)
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Ed
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Equations/421441: I am homeschooled and I have worked on this problem for hours. My mom finally gave me the answer but I don't seem to know how to do the steps correctly to get the answer. If I put my work in here it would take up all the space, so here is the question and the answer. I need the steps.
((x+3)/(x+5)) + ((6) / (x^2 +3x -10)); the answer is ((x^2 + x)/ (x^2 + 3x -10))
1 solutions
Answer 294351 by edjones(7569) on 2011-03-13 07:13:10 (Show Source):
You can put this solution on YOUR website!((x+3)/(x+5)) + ((6)/(x^2 +3x -10))
=((x+3)/(x+5)) + ((6)/((x+5)(x-2))
=(((x+3)(x-2))+6)/((x+5)(x-2))
=(x^2+x-6+6)/(x^2+3x-10)
=(x^2+x)/(x^2+3x-10)
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Ed
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Triangles/421490: The question says: Find x and the measure of each side of the triangle.
This is the problem:
Triangle FGH is equilateral with FG= x+5, GH= 3x-9, and FH= 2x-2. I don't understand how to find the answer.
1 solutions
Answer 294349 by edjones(7569) on 2011-03-13 06:48:10 (Show Source):
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Numbers_Word_Problems/421452: 1. How many 2 digit numbers are possible such that the sum of their digits is equal to twice the difference between the digits?
2. How many 3 digit numbers do not change their value, even if the digits are reversed?
1 solutions
Answer 294348 by edjones(7569) on 2011-03-13 06:42:18 (Show Source):
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