See tutors' answers!

Algebra ->  Tutoring on algebra.com -> See tutors' answers!      Log On


   
By Tutor
 | By Problem Number | 

Tutor:
New! Get regular updates about newly solved problems via algebra.com's RSS system.

Recent problems solved by 'edjones'

edjones answered: 7568 problems
Jump to solutions: 0..29 , 30..59 , 60..89 , 90..119 , 120..149 , 150..179 , 180..209 , 210..239 , 240..269 , 270..299 , 300..329 , 330..359 , 360..389 , 390..419 , 420..449 , 450..479 , 480..509 , 510..539 , 540..569 , 570..599 , 600..629 , 630..659 , 660..689 , 690..719 , 720..749 , 750..779 , 780..809 , 810..839 , 840..869 , 870..899 , 900..929 , 930..959 , 960..989 , 990..1019 , 1020..1049 , 1050..1079 , 1080..1109 , 1110..1139 , 1140..1169 , 1170..1199 , 1200..1229 , 1230..1259 , 1260..1289 , 1290..1319 , 1320..1349 , 1350..1379 , 1380..1409 , 1410..1439 , 1440..1469 , 1470..1499 , 1500..1529 , 1530..1559 , 1560..1589 , 1590..1619 , 1620..1649 , 1650..1679 , 1680..1709 , 1710..1739 , 1740..1769 , 1770..1799 , 1800..1829 , 1830..1859 , 1860..1889 , 1890..1919 , 1920..1949 , 1950..1979 , 1980..2009 , 2010..2039 , 2040..2069 , 2070..2099 , 2100..2129 , 2130..2159 , 2160..2189 , 2190..2219 , 2220..2249 , 2250..2279 , 2280..2309 , 2310..2339 , 2340..2369 , 2370..2399 , 2400..2429 , 2430..2459 , 2460..2489 , 2490..2519 , 2520..2549 , 2550..2579 , 2580..2609 , 2610..2639 , 2640..2669 , 2670..2699 , 2700..2729 , 2730..2759 , 2760..2789 , 2790..2819 , 2820..2849 , 2850..2879 , 2880..2909 , 2910..2939 , 2940..2969 , 2970..2999 , 3000..3029 , 3030..3059 , 3060..3089 , 3090..3119 , 3120..3149 , 3150..3179 , 3180..3209 , 3210..3239 , 3240..3269 , 3270..3299 , 3300..3329 , 3330..3359 , 3360..3389 , 3390..3419 , 3420..3449 , 3450..3479 , 3480..3509 , 3510..3539 , 3540..3569 , 3570..3599 , 3600..3629 , 3630..3659 , 3660..3689 , 3690..3719 , 3720..3749 , 3750..3779 , 3780..3809 , 3810..3839 , 3840..3869 , 3870..3899 , 3900..3929 , 3930..3959 , 3960..3989 , 3990..4019 , 4020..4049 , 4050..4079 , 4080..4109 , 4110..4139 , 4140..4169 , 4170..4199 , 4200..4229 , 4230..4259 , 4260..4289 , 4290..4319 , 4320..4349 , 4350..4379 , 4380..4409 , 4410..4439 , 4440..4469 , 4470..4499 , 4500..4529 , 4530..4559 , 4560..4589 , 4590..4619 , 4620..4649 , 4650..4679 , 4680..4709 , 4710..4739 , 4740..4769 , 4770..4799 , 4800..4829 , 4830..4859 , 4860..4889 , 4890..4919 , 4920..4949 , 4950..4979 , 4980..5009 , 5010..5039 , 5040..5069 , 5070..5099 , 5100..5129 , 5130..5159 , 5160..5189 , 5190..5219 , 5220..5249 , 5250..5279 , 5280..5309 , 5310..5339 , 5340..5369 , 5370..5399 , 5400..5429 , 5430..5459 , 5460..5489 , 5490..5519 , 5520..5549 , 5550..5579 , 5580..5609 , 5610..5639 , 5640..5669 , 5670..5699 , 5700..5729 , 5730..5759 , 5760..5789 , 5790..5819 , 5820..5849 , 5850..5879 , 5880..5909 , 5910..5939 , 5940..5969 , 5970..5999 , 6000..6029 , 6030..6059 , 6060..6089 , 6090..6119 , 6120..6149 , 6150..6179 , 6180..6209 , 6210..6239 , 6240..6269 , 6270..6299 , 6300..6329 , 6330..6359 , 6360..6389 , 6390..6419 , 6420..6449 , 6450..6479 , 6480..6509 , 6510..6539 , 6540..6569 , 6570..6599 , 6600..6629 , 6630..6659 , 6660..6689 , 6690..6719 , 6720..6749 , 6750..6779 , 6780..6809 , 6810..6839 , 6840..6869 , 6870..6899 , 6900..6929 , 6930..6959 , 6960..6989 , 6990..7019 , 7020..7049 , 7050..7079 , 7080..7109 , 7110..7139 , 7140..7169 , 7170..7199 , 7200..7229 , 7230..7259 , 7260..7289 , 7290..7319 , 7320..7349 , 7350..7379 , 7380..7409 , 7410..7439 , 7440..7469 , 7470..7499 , 7500..7529 , 7530..7559 , 7560..7589, >>Next

Rate-of-work-word-problems/469334: 4 men and 10 boys can solve a task in 18 days . how many days will require to solve the task by 12 men and 30 boys?
1 solutions

Answer 321992 by edjones(7569) About Me  on 2011-07-11 19:42:14 (Show Source):
You can put this solution on YOUR website!
triple the workers divides the hours required by 3.
6 days Answer.
.
Ed


Probability-and-statistics/469288: Requesting help on the three problems listed below:
1. A bag contains five cards: the jack, queen, king, ace and ten of clubs. Two cards are to be selected at random without replacement. List the sample space. Find the probability that one of the cards selected is the king.
2. The Cat Lovers' Club has nine members. They need to form a committee consisting of four members to judge the cat show. How many different committees are possible?
3. Two dice are rolled. What is the probability of rolling doubles?
Thanks in advance!!!
1 solutions

Answer 321961 by edjones(7569) About Me  on 2011-07-11 17:46:28 (Show Source):
You can put this solution on YOUR website!
2)
9C4=combination of 9 things taken 4 at a time=9!/((9-4)!*4!)=126 different committees are possible.
.
Ed


Probability-and-statistics/469291: What is the concept of 2 to 5 odds and the probability
example
there is a 2 to 5 odds that we will win the lottery, what is the probability that we wont? and that we will?
1 solutions

Answer 321960 by edjones(7569) About Me  on 2011-07-11 17:43:07 (Show Source):
You can put this solution on YOUR website!
there is a 2 to 5 odds that we will win the lottery.
That means that the odds in favor of winning are 2 to 5 and the odds against are 5 to 2.
The probability that we will win is 2/(5+2) = 2/7; the probability that we wont is 1 - 2/7 = 5/7.
.
Ed


Probability-and-statistics/469218: I have a few problems similar to this and need some direction in solving them please!
a marketing firm asked a random set of married and single men as to how much they were willing to spend for a vacation. At a = .05, is there a difference in the two amounts?
sample size married 50, single 70
mean spending married 260, single 185
sample variance married 4500, single 9000
provided answers:
A) yes, because the test value 5.07 is outside the interval (-1.96, 1.96)
B) no, because the test value 2.00 is outside the interval (-1.96, 1.96)
C) no, because the terst value 0.34 is inside the interval (-1.96, 1.96)
D) yes, because the test value 2.00 is inside the interval (-1.96, 1.96)


1 solutions

Answer 321953 by edjones(7569) About Me  on 2011-07-11 17:32:54 (Show Source):
You can put this solution on YOUR website!
S=single, M=married

.
z=%28mu%5Bm%5D-mu%5Bs%5D%29%2Fsigma=%28260-185%29%2F15=5.07
A)
.
Ed


Probability-and-statistics/469226: Please help me to solve: Suppose that 2 cards are dealt from a standard 52-card poker deck. Let A be the event that the sum of the 2 cards is 8(assume that aces equal 1) How many outcomes are in A?
This is how I started: Combinations that equal 8: A+7, 2+6, 3+5, 4+4, 5+3, 6+2, 7+A. Considering there are 4 cards for each number and add them together is 8 cards per set of combinations. There are 7 combinations, so 7*8=56. How does that sound?
1 solutions

Answer 321941 by edjones(7569) About Me  on 2011-07-11 16:34:16 (Show Source):
You can put this solution on YOUR website!
There are 4 aces and 4 sevens=4*4=16
Remember that we are looking for combinations not permutations. The order in which
the cards are dealt is not important.
There are 16 possible combinations of A,7.
Another 16 for 6,2 and 16 for 3,5
16*3=48
4C2=6 a special case for 4,4
.
48+6=54
You were close.
.
Ed


Probability-and-statistics/469239: The question is: A poker deck consisting of 52 cards, representing 13 denomination and 4 suits. A 5 card hand is called a flush if all cards are the same suit but not all 5 denominations are consecutive. You have drawn a 2 of hearts,3 of hearts, 7 of hearts, jack of hearts and a queen of hearts. Let N be the set of 5 cards in hearts that are not flushes. How many outcomes are in N?
I am assuming we need to find the probability of having a flush in hearts.
Card 1: .25, card 2:.24, card 3: .22, card 4: .20 and card 5: .19.
.25*.24*.22*.20*.19=.0005016
I don't know my next steps.
1 solutions

Answer 321932 by edjones(7569) About Me  on 2011-07-11 15:24:35 (Show Source):
You can put this solution on YOUR website!
Let N be the set of 5 cards in hearts that are not flushes.
The set N is called a straight flush. They beat any other poker hand including a flush.
There are 10 possible straight flushes in a suit A2345 to TJQKA.
There are 4 different suits.
10C1 * 4C1 = 40 possible straight flushes.
.
Ed


Probability-and-statistics/469011: Can a tutor so kindly review these problems and show me how to do them step by step?
Suppose the scores of certain standardized test are normally distributed with mean 500 and standard
deviation 60.
8. (1 point) What percent of the test takers have a score of 440 or less? Round answer to four places after
the decimal point.
9. (1 point) What percent of the test takers have a score of 590 or more? Round answer to four places
after the decimal point.
10. (1 point) What percent of the test takers have a score between 440 and 590? Round answer to four
places after the decimal point.
11. (1 point) Suppose a college will only admit students who score in the top 20% among all test takers,
what will be the minimum required score be? Round answer to the nearest whole number.
1 solutions

Answer 321788 by edjones(7569) About Me  on 2011-07-10 20:23:18 (Show Source):
You can put this solution on YOUR website!
8.
z=(440-500)/60=-60/60=-1
.1587=15.87% of the test takers have a score of 440 or less.
.
11.
Above .20 is 0.8416
z=0.8416=(x-500)/60
x-500=80.496
x=580.496=580
.
Ed


Money_Word_Problems/468974: when equal amounts are invested in each of three accounts paying 7%, 8% and 10.5% interest one years combined interest is 1,007.25. how much was invested in each account
1 solutions

Answer 321781 by edjones(7569) About Me  on 2011-07-10 20:10:30 (Show Source):
You can put this solution on YOUR website!
.07x+.08x+.105x=.255x
.255x=1007.25
x=3,950
3950/3 was invested in each account.
.
Ed


expressions/469009: determine wether -8 is a solution of the equation 6x=18
1 solutions

Answer 321779 by edjones(7569) About Me  on 2011-07-10 19:54:44 (Show Source):


Probability-and-statistics/468313: 15. A set of final examination grades in a home economics course is normally distributed, with a mean of 73 and standard deviation of 6.
a. What is the probability that a student scored below 91 on exam?
b. What is the probability that a student scored between 60-80 on the exam?
c. The probability is 5% that a student taking the test scores higher than what grade?
d. If the professor grades on a curve by giving the top 10% A’s regardless of scores, are you better off with a grade of 80 on this exam or 64 on another exam, where the mean is 60 and the standard deviation is 3? Show your answer statistically.
Please Help!

1 solutions

Answer 321512 by edjones(7569) About Me  on 2011-07-09 07:12:14 (Show Source):
You can put this solution on YOUR website!
a) z=(91-73)/6=18/6=3
.9987 the probability that a student scored below 91 on exam.
.
b) z=(60-73)/6=-13/6=-2.1667
z=(80-73)/6=13/6=2.1667
.9697 the probability that a student scored between 60-80 on the exam.
.
c) 1.6949=(x-73)/6
x-73=10.1694
x=83.2
.
d) z=(64-60)/3=4/3=1.3333
z=(80-73)/6=13/6=2.1667
.
Ed


Rational-functions/468404: Please help me find the domain to this function
+g%28x%29=sqrt%287-3x%29
1 solutions

Answer 321425 by edjones(7569) About Me  on 2011-07-08 18:57:04 (Show Source):
You can put this solution on YOUR website!
g(x)=sqrt(7-3x)
7-3x>=0 Can't have sqrt of a number less than 0.
-3x>=-7
x<=7/3
.
X(-infinity, 7/3]
.
Ed


Probability-and-statistics/468423: Forty-eight salesmen attended a sales meeting. As door prizes, the organizers of the meeting are giving away one iPod, one iPhone, and one Wii. In how many different ways can the three winners be chosen? (Keep in mind that it matters which prize a person wins.)
1 solutions

Answer 321423 by edjones(7569) About Me  on 2011-07-08 18:50:53 (Show Source):
You can put this solution on YOUR website!
nPr=n!/(n-r)!
=48!/(48-3)!
=(48*47*46*45!)/45!
=48*47*46
=103776
.
Ed


Geometry_Word_Problems/468383: How did you get 4x?
"Two angles of a triangle have equal measures, but the third angle's measure is 36° less than the sum of the other two. Find the measure of each angle of the triangle."
Theo: "Draw a triangle and label is ABC.
Let angle A = x
let angle B = x
let angle C = 2x - 36
2x - 36 means that angle C is 36 degrees less than the sum of angle A and B.
Since the sum of the interior angles of a triangle is 180 degrees, then 2x + 2x - 36 = 180.
combine like terms in that equation and you get 4x - 36 = 180
add 36 to both sides of that equation and you get 4x = 216
divide both sides of that equation by 4 and you get x = 54 degrees
angle A = 54 degrees
angle B = 54 degrees
angle C = 108 - 36 = 72 degrees
54 + 54 + 72 = 108 + 72 = 180 degrees so the angles are good because they add up to 180 degrees and the third angle is 36 degrees less than the sum of the other 2."
1 solutions

Answer 321420 by edjones(7569) About Me  on 2011-07-08 18:47:20 (Show Source):
You can put this solution on YOUR website!
How did you get 4x?
By adding x+x+(2x-36)
=4x-36
.
Ed


Probability-and-statistics/468397: Suppose that the New England Colonials baseball team is equally likely to win any particular game as not to win it. Suppose also that we choose a random sample of 20 Colonials games.
1. Estimate the number of games in the sample that the Colonials win by giving the mean of the relevant distribution (that is, the expectation of the relevant random variable). Do not round your response.
2. Quantify the uncertainty of your estimate by giving the standard deviation of the distribution. Round your response to at least three decimal places.
1 solutions

Answer 321414 by edjones(7569) About Me  on 2011-07-08 18:28:56 (Show Source):


Rational-functions/468408: Please help me find the domain to this function
g%28x%29=sqrt%28x%5E2-2x-8%29
1 solutions

Answer 321413 by edjones(7569) About Me  on 2011-07-08 18:23:28 (Show Source):
You can put this solution on YOUR website!
g(x)=sqrt(x^2-2x-8) The square root cannot be less than zero.
(x-4)(x+2)=0
x=4, x=-2
(-infinity, -2] U [+2, infinity)
.
Ed


test/468228: The grounskeeper is replacing the turf on a football field. His measurements of the field are 130 yards by 60 yards. The actual measurements are 120 yards by 54 yards. Which expression represents the relative error in the measurement? (A). (120)(54)/(130)(60)-(120)(54). (B). (130)(60)-(120)(54)/(120)(54). (C). (130)(60)/(130)(60)-(120)(54). (D). (130)(60)-(120)(54)/(130)(60)
1 solutions

Answer 321272 by edjones(7569) About Me  on 2011-07-08 00:45:26 (Show Source):


Rate-of-work-word-problems/468223: I need help understanding how to solve and write this problem. I also want to understand the concept of it.
A roofer can shingle a house in 12 hours. He starts a house with an apprentice and they work 3 hours until the roofer falls off and is carried away. It takes the apprentice another 12 hours to finish. How long would it take the apprentice working alone to do an entire home?
1 solutions

Answer 321271 by edjones(7569) About Me  on 2011-07-08 00:41:19 (Show Source):
You can put this solution on YOUR website!
The roofer can do 1/12 the job in 1 hr.
The apprentice can do the job in x hrs. and can do 1/x of the job in 1 hr.
3(1/12 + 1/x) + 12/x = 1 (job)
(3/12 + 3/x) + 12/x = 1
1/4 + 3/x + 12/x = 1
x+12+48=4x multiply each side by 4x.
3x=60
x=20 hrs time it would take the apprentice working alone to do an entire home.
.
Ed


Exponents/468216: define a rational exponent
1 solutions

Answer 321266 by edjones(7569) About Me  on 2011-07-07 23:05:08 (Show Source):
You can put this solution on YOUR website!
an exponent in fraction form
.
a^(3/2) is an example.
.
Ed


Radicals/468186: Hello. Can you please help me?
I need to make v the subject of the following formula (Einstein's theory of relativity). It's a fraction involving m followed by a little O as numerator, with a radical in the denominator.
m= (mo)/ (radical around the following:) 1-(v/c)^2
Thank you so much!
1 solutions

Answer 321264 by edjones(7569) About Me  on 2011-07-07 22:59:00 (Show Source):
You can put this solution on YOUR website!
Solve for v.
m=(Mo)/sqrt( 1-(v^2/c^2))
m*sqrt( 1-(v^2/c^2))=Mo
sqrt( 1-(v^2/c^2))=Mo/m
1-(v^2/c^2)=Mo^2/m^2
v^2/-c^2=(mo^2/m^2)-1
v^2=-c^2((mo^2/m^2)-1)
v=sqrt(m^2-Mo^2)*|c/m|
.
Ed


Mixture_Word_Problems/468189: 240 is to 360 as x is to 1200.
1 solutions

Answer 321260 by edjones(7569) About Me  on 2011-07-07 22:29:14 (Show Source):
You can put this solution on YOUR website!
240/360=x/1200
x=800
.
Ed


Permutations/468190: Each Thursday, Alan takes a break from studies and eats dinner with his grandparents. On one occasion, his choice for dessert is peppermint or vanilla ice cream with chocolate, strawberry, caramel, or pineapple topping.
(a) How many ways can Alan choose one flavor of ice cream and one topping?
1 ways
(b) How many ways can Alan choose one flavor of ice cream and two toppings?

1 solutions

Answer 321258 by edjones(7569) About Me  on 2011-07-07 22:26:59 (Show Source):
You can put this solution on YOUR website!
a) 2*4=8 ways
.
b) 2*4*3=24 ways as long as the 2 toppings are different.
.
Ed


Equations/468211: 7b-5+b=2b-4+b-6
1 solutions

Answer 321253 by edjones(7569) About Me  on 2011-07-07 22:17:44 (Show Source):
You can put this solution on YOUR website!
7b-5+b=2b-4+b-6
8b-5=3b-10
5b=-5
b=-1
.
Ed


Geometric_formulas/468193: Lost and confused: Please help me see where I messed up!
Glenda wants to glue glitter over a piece of felt shaped like a parallelogram with a height of 48in and a base of 26in. If the glitter costs $1.00 per square ft, how much will it cost to cover the felt?
A. $34.67
B. $1248
C. $104.00
D. $8.67
The correct answer is D. I chose B. I used the formula: A=bh. I do not see how they got $8.67????
1 solutions

Answer 321252 by edjones(7569) About Me  on 2011-07-07 22:14:45 (Show Source):
You can put this solution on YOUR website!
48*26=1248 in^2
1 ft^2 = 144 in^2
1248/144=8.67 ft^2
8.67*$1.00=$8.67 D
.
Ed


Probability-and-statistics/468200: Let Z be a standard normal random variable. Calculate the following probabilities using the calculator provided. Round your responses to at least three decimal places.
P (Z > - 1.51) =
P (Z ≤ 0.88) =
P (0.87 < Z < 1.50) =
1 solutions

Answer 321251 by edjones(7569) About Me  on 2011-07-07 21:55:47 (Show Source):
You can put this solution on YOUR website!
P (Z > - 1.51) =0.934
.
P (Z ≤ 0.88) =0.811
.
P (0.87 < Z < 1.50) =0.125
.
Ed


expressions/467973: Could Someone please help, and show me step by step if possible so that I can complete the next one on my own. Thanks.
Evaluate. Please show all of your work.
-5 ÷ m^2 – 2(m – 2), for m = 1

1 solutions

Answer 321172 by edjones(7569) About Me  on 2011-07-07 16:00:27 (Show Source):
You can put this solution on YOUR website!
-5 ÷ m^2 – 2(m – 2), for m = 1
=-5/1^2 - 2(1-2)
=-5/1 - 2(-1)
=-5-(-2)
=-5+2
=-3
.
Ed


Linear-equations/468094: how to solve -20s+42+5(4s-8)=0
1 solutions

Answer 321171 by edjones(7569) About Me  on 2011-07-07 15:53:55 (Show Source):
You can put this solution on YOUR website!
-20s+42+5(4s-8)=0
-20s+42+20s-40=0
-20s+20s=-2
0=-2 there is no answer.
.
Ed


Functions/467989: Find the domain of the following:

a) f(t)= 5.4e^t
Answer and explain how you obtained your answer.


b) g(x)=log(x+3)
Answer and explain how you obtained your answer.


c) g(x)=2^x
Answer and explain how you obtained your answer.


d) g(t)=ln(t-1)
Answer and explain how you obtained your answer.



1 solutions

Answer 321169 by edjones(7569) About Me  on 2011-07-07 15:51:07 (Show Source):
You can put this solution on YOUR website!
a) all real numbers.
.
b)(-3, infinity)
.
c) all real numbers
.
d)(1, infinity)
.
Ed


Rectangles/467994: if a square room measures 17 feet on both sides what is the perimeter and area
1 solutions

Answer 321167 by edjones(7569) About Me  on 2011-07-07 15:42:47 (Show Source):
You can put this solution on YOUR website!
p=4*17=68 ft
A=17^2=289 ft^2


Linear-equations/467990: 2x-1<4x+3
1 solutions

Answer 321166 by edjones(7569) About Me  on 2011-07-07 15:41:00 (Show Source):
You can put this solution on YOUR website!
2x-1<4x+3
-2x<4
x>-2
.
Ed


Linear-systems/468075: y=-x+3
y=x+1
1 solutions

Answer 321165 by edjones(7569) About Me  on 2011-07-07 15:36:15 (Show Source):
You can put this solution on YOUR website!
y=-x+3
y=x+1
-------add
2y=4
.
y=2
x=1
.
Ed


Numbers_Word_Problems/468091: A number is decreased by 11, and the result it multipled by 2. the final answer is 20. What is the number?
1 solutions

Answer 321164 by edjones(7569) About Me  on 2011-07-07 15:33:22 (Show Source):
You can put this solution on YOUR website!
2(x-11)=20
2x-22=20
2x=42
x=21
.
Ed