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edjones answered: 7568 problems
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Find the size of the angles.
A
B
C
1 solutions
Answer 278186 by edjones(7569)   on 2011-01-08 14:01:42 (Show Source):
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Miscellaneous_Word_Problems/391973: Alice and Corinne stand back-to-back. They each take 10 steps in opposite directions away from each other and stop. Alice then turns around, walks toward Corinne, and reaches her in 17 steps. The length of one of Alice’s steps is how many times the length of one of Corinne’s steps? (All of Alice’s steps are the same length and all of Corinne’s steps are the same length.)
1 solutions
Answer 278183 by edjones(7569) on 2011-01-08 13:42:50 (Show Source):
You can put this solution on YOUR website!When A takes 10 steps back she is where she started. Her 7 steps = C's 10 steps.
the length of A's step is 10/7 that of one of C.
10/7 answer.
.
Ed
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Probability-and-statistics/391988: 56. Assume the likelihood that any flight on Northwest Airlines arrives within 15 minutes of
the scheduled time is .90. We select four flights from yesterday for study.
a. What is the likelihood all four of the selected flights arrived within 15 minutes of the
scheduled time?
b. What is the likelihood that none of the selected flights arrived within 15 minutes of
the scheduled time?
c. What is the likelihood at least one of the selected flights did not arrive within 15 minutes
of the scheduled time?
1 solutions
Answer 278175 by edjones(7569) on 2011-01-08 13:22:50 (Show Source):
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Linear-systems/391586: below are a rectangle and a right triangle.
The perimeter of the rectangle is 34 cm. The perimeter of the triangle is 30 cm. Find the values of m and n.
On the right triangle, the base is n and the side is m. The slope however is n+1. The rectangles base is n and the side is m.
1 solutions
Answer 277855 by edjones(7569) on 2011-01-07 01:40:47 (Show Source):
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Permutations/391588: In how many ways can you arrange the letters of the word 'think' so that the 't' and the 'h' are separated by at least one other letter? Use the indirect method.
1 solutions
Answer 277853 by edjones(7569) on 2011-01-07 01:24:57 (Show Source):
You can put this solution on YOUR website!Let's make them one letter, the "th" letter. 4!=24
Let's make them one letter, the "ht" letter. 4!=24
24*2=48 ways they are not separated by a letter.
5!=120 possible arrangements of the word "think".
120-48=72 ways you can arrange "think" so the t and h are seperated by at least one letter.
.
Ed
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Geometric_formulas/391589: Sixteen students went on a week-long hiking trip. They brought with them 320 specially baked, protein-rich cookies. What is the ratio of cookies to students?
1 solutions
Answer 277850 by edjones(7569) on 2011-01-07 01:09:35 (Show Source):
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Equations/391595: write the equation for two times the sum of a number and three is equal to fifteen.
I wrote 2(n+3)=15 but do not think it is correct because when I checked the answer into the equation my answer did not equal fifteen.
1 solutions
Answer 277846 by edjones(7569) on 2011-01-07 00:58:56 (Show Source):
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Polynomials-and-rational-expressions/391606: I'm hoping someone can help me with this. Here is my problem:
x^3-2x^2-7x-4=0
Please note, the "3" and the "2" are exponents.
I have to a)list all possible rational roots
b)use synthetic division to test the possible rational roots and find an actual root
c)use the quotient from part b to find the remaining roots and solve the equation.
Ok...Here's what I have so far:
For part a) my POSSIBLE rational roots, obtained by dividing the factors of the constant term/lead coefficient are; {+-1.+-2,+-4}
For part b) I tested them via synthetic division and found that
{-1,2,4} are my ACTUAL roots.
Ok...HERE'S what I don't get: First, let me ask a silly question. If I have used all my POSSIBLE roots and found ACTUAL roots, how can any roots still be remaining? Also...WHICH quotient am I supposed to use??!!! I would be very grateful for help and clarification of part c of this problem! I need to know how to find the "remaining roots", then how to use it to solve my polynomial. Thank you to whomever responds!
1 solutions
Answer 277840 by edjones(7569) on 2011-01-07 00:32:47 (Show Source):
You can put this solution on YOUR website!+-1.+-2,+-4 are the possible roots.
The whole purpose of the sythetic division is to break the polynomial into smaller pieces so as to find the other roots and solve the equation. In this case if we can get one root then we will have a quadratic left and our troubles are over.
x^3-2x^2-7x-4 / x-4 = x^2+2x+1 This is the quotient.
x^2+2x+1=(x+1)(x+1)
So (x+1)(x+1)(x-4)=0
x=-1 and x=4 These are the zeros of the equation.
-1, -1, and 4 are the roots of the equation. It cannot have more than three roots because x^3 has the exponent 3.
.
Ed
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Evaluation_Word_Problems/391616: At the endof the 2000 baseball season, the New York Yankees and the Cincinnati Reds had won a total of 31 World Series. The Yankees had won 5.2 times as many World Series as the Reds. How many World Series did each team win?
1 solutions
Answer 277832 by edjones(7569) on 2011-01-06 23:15:33 (Show Source):
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Probability-and-statistics/391621: We have 2 girls and 4 boys to be seated ina 6-seat row at the movie theater. What is the probability that the two people at each end of the row were both boys or both girls? Answer should be in common fraction.
My approach to this problem:
Total possibilities of boys and girls is 4! * 2!
No of success outcomes: for Girls: 2! * 2!
for Boys : 4
p(both boys or both girls)= (4 + 2!*2!)/4! * 2!
Is my approach correct?
1 solutions
Answer 277828 by edjones(7569) on 2011-01-06 22:53:29 (Show Source):
You can put this solution on YOUR website!nPr=permutations of n things taken r at a time=n!/(n-r)!
.
a girl at either end:
2P2*4!=48 ways (only 2 possible arrangements for the girls and 4! for the boys.)
.
a boy at either end:
4P2 * 4!
=12*24
=288 ways
.
Probability=(48+288)/6!
=336/720
=7/15
.
Ed
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Probability-and-statistics/391642: 100% of the normal distribution is within how many standard deviations of the mean?
1 solutions
Answer 277825 by edjones(7569) on 2011-01-06 22:16:44 (Show Source):
You can put this solution on YOUR website!Since the space between the graph and the baseline gets smaller but never touches as the graph moves away from the mean to either side then the number of standard deviations approach infinity as the lines approach becoming one.
.
Ed
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Rate-of-work-word-problems/390599: Solve the following problem using the 5 step method
It takes Tim 4 minutes to build a snowman and his younger brother Jim 12 minutes to build a snowman. How long will it take them to build a snowman working together?
1 solutions
Answer 277026 by edjones(7569) on 2011-01-04 15:39:50 (Show Source):
You can put this solution on YOUR website!Let t=time it takes the to build a snow man together.
Tim can do 1/4 the job in 1 minute, jim can do 1/12 the job in 1 minute.
1/4 + 1/12 = 1/t
3/12 + 1/12 = 4/12 = 1/3
t=3 min
.
Ed
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