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 test/751858: 3 ( log 5 - log 3 ) - ( log 5 - 2 log 6 ) = 2 - log n , find n. 1 solutions Answer 457457 by nerdybill(6959)   on 2013-05-23 09:40:57 (Show Source): You can put this solution on YOUR website!3 ( log 5 - log 3 ) - ( log 5 - 2 log 6 ) = 2 - log n , find n. . 3 ( log 5 - log 3 ) - ( log 5 - 2 log 6 ) = 2 - log n 3log 5 - 3log 3 - ( log 5 - 2 log 6 ) = 2 - log n log 5^3 - log 3^3 - ( log 5 - 2 log 6 ) = 2 - log n log 125 - log 27 - ( log 5 - 2 log 6 ) = 2 - log n log 125 - log 27 - ( log 5 - log 6^2 ) = 2 - log n log 125 - log 27 - ( log 5 - log 36 ) = 2 - log n log 125 - log 27 - log 5 + log 36 = 2 - log n log 125/27 - log 5 + log 36 = 2 - log n log 125/(27*5) + log 36 = 2 - log n log (125*36)/(27*5) = 2 - log n log (125*36)/(27*5) = 2 - log n log (125*36)/(27*5) - 2 = -log n -[log (125*36)/(27*5) - 2] = log n 10^(-[log (125*36)/(27*5) - 2]) = n 10^(-[log (4500)/(27*5) - 2]) = n 10^(-[log 900/27 - 2]) = n 10^(-[log 100/3 - 2]) = n 10^(-[1.52287874528 - 2]) = n 10^(0.4771212547196624372950) = n 3 = n
 Travel_Word_Problems/526926: what is the speed if a car traveled 400km in 5hr1 solutions Answer 457456 by josh's girl(6)   on 2013-05-23 09:31:34 (Show Source): You can put this solution on YOUR website!80km
 test/751886: If the odds of winning the lotto are 1 in 195,000,000 what are the odds if I buy 360 tickets? 1 solutions Answer 457455 by MathLover1(6634)   on 2013-05-23 09:12:31 (Show Source): You can put this solution on YOUR website!The odds are therefore halved to in ( in ). I buy one ticket at first - a chance. is %. I then buy tickets to increase my chances - a chance is %.
 Systems-of-equations/751894: 2x + 8y = 6 -5x + -20y = -15 solve using addition 1 solutions Answer 457454 by JoeTaxpayer(129)   on 2013-05-23 09:10:31 (Show Source): You can put this solution on YOUR website!2x + 8y = 6 -5x + -20y = -15 Let's multiply the first equation (both sides) by 5 and the second by 2: 10x+40y=30 -10x-40y=-30 These are the same line, the 'solution' is the line itself, all points. Simplify to x+4y=3 if you'd like.
 Polynomials-and-rational-expressions/751893: How do I factor this cube function? ((x^3)-((8x)^2)- (16x))1 solutions Answer 457453 by JoeTaxpayer(129)   on 2013-05-23 09:06:07 (Show Source): You can put this solution on YOUR website! First, factor out an X The solution to the quadratic is real, but not integers. This is the simplest factorization.
 Triangles/751884: A triangle has 2 sides of length 7.4 and 17.3. Given that the third side has an integer length, what is the largest possible length that it could be? 1 solutions Answer 457452 by JoeTaxpayer(129)   on 2013-05-23 08:44:40 (Show Source): You can put this solution on YOUR website!24 As the angle between the two side you offered approaches 180º the length of that third side reaches a maximum of 'under' 7.4+17.3= 24.7 so 24 is the higher integer.
 Percentage-and-ratio-word-problems/751873: Which Came First: The Hen or the Egg?1 solutions Answer 457451 by MathLover1(6634)   on 2013-05-23 07:38:16 (Show Source): You can put this solution on YOUR website! A literal answer is somewhat obvious to some people, as egg-laying species pre-date the existence of chickens. To others, the chicken came first, seeing as chickens are merely domesticated Red Junglefowls. However, the metaphorical view sets a metaphysical ground to the dilemma. To better understand its metaphorical meaning, the question could be reformulated as: "Which came first, X that can't come without Y, or Y that can't come without X?" An equivalent situation arises in engineering and science known as circular reference, in which a parameter is required to calculate that parameter itself. The term "chicken-and-egg problem" is further commonly used to describe a situation that is not a philosophical dilemma, but one in which it is impossible to reach a certain desired outcome because a necessary precondition is not satisfied, while to meet that precondition in turn requires that the desired outcome has already been realized. For example, it has been argued that the transformation to alternative fuels for vehicles faces a chicken-and-egg problem: "it is not economical for individuals to purchase alternative fuels absent sufficient refueling stations, and it is not economical for fuel dealers to open stations absent sufficient alternative fuel vehicles".[23] This is closely related to the economic concept of vicious circle, but in this kind of situation one that becomes a virtuous circle upon reaching a tipping point. A virtuous circle and a vicious circle (also referred to as virtuous cycle and vicious cycle) are economic terms. They refer to a complex chain of events that reinforces itself through a feedback loop.[1] A virtuous circle has favorable results, while a vicious circle has detrimental results. Both circles are complexes of events with no tendency towards equilibrium (at least in the short run). Both systems of events have feedback loops in which each iteration of the cycle reinforces the previous one (positive feedback). These cycles will continue in the direction of their momentum until an external factor intervenes and breaks the cycle. The prefix "hyper-" is sometimes used to describe these cycles if they are extreme. The best-known example of a vicious circle is hyperinflation. source:Wikipedia
 Linear-systems/751835: 5x-7y=11 3x=2y1 solutions Answer 457450 by malglu(13)   on 2013-05-23 07:19:40 (Show Source): You can put this solution on YOUR website!reaarange the sums 5x -7y =11 3x - 2y = 0 multiply the first by 3 and the secone by 5 15x - 21y = 33 15x -10y = 0 minus the second equation from the first -11y = 33 y=-3 sunsitute this in any of the equations to get x x=-2
 Problems-with-consecutive-odd-even-integers/751839: find four consecutive integers such that if the sum of the first and third is multiplied by 2, the result is 20 less than three times the fourth1 solutions Answer 457449 by malglu(13)   on 2013-05-23 07:15:57 (Show Source): You can put this solution on YOUR website!let the numbers be x x+1 x+2 and x+3 as they are consecutive using algebra we can wrote what we know as 2(x + (x+2)) = 3(x+3) -20 so 4x +4 = 3x -11 x= -15 so the numbers are -15 -14 -13 -12
 Percentage-and-ratio-word-problems/751840: A one year investment yields a return of 15%. The cash returned from the investment,including principal and interest is \$2070. What is the interest ?1 solutions Answer 457448 by malglu(13)   on 2013-05-23 07:12:21 (Show Source): You can put this solution on YOUR website!what we know is that 115% of x (the principle invested) is 2070 115/100 * x = 2070 this becomes x=207000/115 which is 1800 so the principle invested is 1800 and the interest earned is 270
 Probability-and-statistics/751867:   A new skin cream is being tested to treat a skin rash.   None of the first 5 patients on the new treatment were cured.  If the efficacy of the treatment is actually 30%, what is the probability of this outcome?1 solutions Answer 457447 by reviewermath(525)   on 2013-05-23 07:10:27 (Show Source): You can put this solution on YOUR website!probability = =
 Probability-and-statistics/751869:   A data entry person has an accuracy rate of 99%, i.e. he enters 99 out of a 100 data fields correctly (a data field is a variable value, e.g. age, sex, etc).  He has to enter 20 questionnaires, with 20 data fields each.  What is the probability that his data entry (2 decimal places only) will be error free? 1 solutions Answer 457446 by reviewermath(525)   on 2013-05-23 07:08:04 (Show Source): You can put this solution on YOUR website!probability = =
 Numbers_Word_Problems/751847: if twice the quantity of x+6 is divided by negative 7, the result is 6 what would be the negative nuber1 solutions Answer 457445 by malglu(13)   on 2013-05-23 07:07:56 (Show Source): You can put this solution on YOUR website!i think this is what you mean 2 * (x+6) all divided by minus 7 = 6 multuply both sides by minus 7 2(x+6) = -42 2x +12 =-42 2x = -54 divide by 2 x=-27
 Word_Problems_With_Coins/751866: A bank teller notices that he has 50 coins all of which are 5c and 10c pieces. He finds that the value of the coins is \$4.20. How many of each must he have? 2 solutions Answer 457444 by malglu(13)   on 2013-05-23 07:03:49 (Show Source): You can put this solution on YOUR website!there are 50 coins altogether let n = the amount of 5c pieces and d the 10c pieces so n+d =50 rearranging d=50-n now the value of n = 5 (cents), and d =10 (cents) so 5n +10d = 420 (cents) substituting d=50-n instead of d in the equation 5n + 10 (50-n) = 420 multiplying out and rearranging you get 80/5 =n so n = 16 therefore d = 34 Answer 457442 by Cromlix(353)   on 2013-05-23 06:56:44 (Show Source): You can put this solution on YOUR website!x = 5c: y = 10c x + y = 50.......1 5x + 10y = 420......2 Multiply (1) by 10 10x + 10y = 500.....3 5x + 10y = 420.....2 Subtract 2 from 3 5x = 80 x = 16 Substitute x = 16 into Eqn (1) 16 + y = 50 y = 50 - 16 y = 34 Therefore there are 16 x 5c and 34 x 10c Hope this helps. :-)
 Equations/751868: 5n-6=8n+61 solutions Answer 457443 by Cromlix(353)   on 2013-05-23 06:58:50 (Show Source): You can put this solution on YOUR website!5n - 6 = 8n + 6 Collect like terms 5n - 8n = 6 + 6 -3n = 12 n = -4 Hope this helps :-)
 Linear_Equations_And_Systems_Word_Problems/751842: if the mearures pf wall is 8m*5m*2m and a brick measure is 50cm *30cm*20cm.find the numbr of bricks in this wall?1 solutions Answer 457441 by Cromlix(353)   on 2013-05-23 06:50:40 (Show Source): You can put this solution on YOUR website!Convert wall dimensions to centimeters. 800 x 500 x 200 Multiply together = 80,000,000 cm^3 Multiply brick dimensions 50 x 30 x 20 = 30,000 Divide 80,000,000/30,000 = 266.6 bricks Hope this helps :-)
 Numbers_Word_Problems/751864: Ninety-eight is at most three times the sum of a number x and five 1 solutions Answer 457440 by malglu(13)   on 2013-05-23 06:48:10 (Show Source): You can put this solution on YOUR website!write 3 (x+5) is less then or equal to 98 so 3x +15 is less then o equl to 98 -15 3x is less then or equal to 83 divide by 3 x is less then or equal to 83/3
 test/751857: What's 5×5?1 solutions Answer 457439 by Cromlix(353)   on 2013-05-23 06:34:21 (Show Source): You can put this solution on YOUR website!5 x 5 = 25
 Radicals/749990: b cube root 24a^5b + 3a cube root 81a^2b^41 solutions Answer 457438 by malglu(13)   on 2013-05-23 06:14:45 (Show Source): You can put this solution on YOUR website!b cube root 24a^5b + 3a cube root 81a^2b^4 24 = 8 *3 8 = 2^3 a^5 = a^3 *a^2 81 = 27*3 27 = 3^3 b^4 = b^3 * b using that info rewrite the expression b cube root (2^3 *3 *a^3 * a^2 *b) + 3 cube root (3^3 *3 *a^2 * b^3 *b) b * 2 *a cube root (3ba^2) + 3 * 3 *b cube root (3ba^2) the expression now becomes 2ba cube root (3ba^2) + 9b cube root (3ba^2) which can be simplified into (2ba + 9b)cube root (3ba^2)
 Radicals/749992: 5/root 61 solutions Answer 457437 by malglu(13)   on 2013-05-23 06:06:35 (Show Source): You can put this solution on YOUR website!never leave a radical as a denominator. multiply the fraction by sqrt (6)/sqrt (6) which is of course = to 1 5 * sqrt 6/sqrt 6 * sqrt 6 this then becomes 5 sqrt (6) / 6
 Radicals/750370: Could I please have help solving this equation? w = Thanks! 1 solutions Answer 457436 by malglu(13)   on 2013-05-23 06:04:32 (Show Source): You can put this solution on YOUR website!square bothe sides w^2 = 7w rearrange w^2-7w=0 thus w(w-7)=0 w=0 or 7
 Radicals/751279: √5x-x=01 solutions Answer 457435 by malglu(13)   on 2013-05-23 06:03:11 (Show Source): You can put this solution on YOUR website!not sure if you meant this sqrt (5x) - x =0 if so, then sqrt (5x) = x sqaure bothe sides 5x = x^2 rearrange x^2 -5x =0 so x(x-5)=0 x = 0, or 5
 Radicals/751669: Simplify the following: 3(the square root of 75) I have gotten two answers and I have no clue which one is right. 1. 2. or 1 solutions Answer 457434 by malglu(13)   on 2013-05-23 05:59:37 (Show Source): You can put this solution on YOUR website!Simplify the following: 3(the square root of 75) I have gotten two answers and I have no clue which one is right. 1. 2. or 3 sqrt (75) = 3 sqrt (25) sqrt (3) sqrt (25) = 5 so take the root out and multiply by the 3 so 3*5 sqrt (3) 15 sqrt (3) is the answer