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Question 1140893: In a class in which the final course grade depends entirely on the average of four equally weighted 100-point tests, Paul has scored 82, 88, and 87 on the first three. What range of scores on the fourth test will give Paul a C for the semester (an average between 70 and 79, inclusive)? Assume that all test scores have a non-negative value.
**Express your answer in interval notation**
Click here to see answer by greenestamps(13200)

Question 1140927: Maxis taking a cross-country road trip. Gas prices vary as the friends travel across the US from $4 dollars per gallon on the east coast, to $3 in the mid-US, to $5 on the west coast. If they used twice as much gas in the mid-US than on either coasts combined, and they spend $515 on gas to purchased 150 gallons of gas, how many gallons of gas did they buy at each price?
Click here to see answer by Boreal(15235)

Question 1141180: Find all the solutions of the following systems of equations if possible. If a system has no solution, explain why it does not.
2x-5y=7,
3x+4y=2.
Click here to see answer by Theo(13342)

Question 1141199: What is the graph of the system?
y < -x - 1
y > x + 4
Click here to see answer by Theo(13342)

Question 1141404: The manager of an apartment complex is also a tenant. He pays only three-fourths of the monthly rent that each of the remaining 7 tenants pays. Each month, a total of $6,200 in rent is paid by the 8 occupants. How much rent does the manager pay?
Write a system of two equations in two variables to solve the problem.
A law firm hired several workers to help finish a large project. From the following billing records, determine the daily fee charged by the employment agency for a clerk-typist and for a computer programmer. (Assume a = 702 and b = 1000.)
Write a system of two equations in two variables to solve the problem.
How many pounds of each candy shown must be mixed to obtain 100 pounds of candy that would be worth $4.40 per pound? gummy bears $3.50 lb and jelly beans $5.50 lb
Click here to see answer by josgarithmetic(39617)

Question 1141464: 8a+5c=180.5
Click here to see answer by josgarithmetic(39617)

Question 1141541: If the solution of the system
Ax + By = −16
Bx − Ay = −52
is (−5, 7),
what are the values of the constants A and B?
Click here to see answer by Alan3354(69443)

Question 1141694: What are the coordinates for the point where
the line whose equation is 2x+y=11 crosses
the line whose equation is y=x-1
thanks
Click here to see answer by josgarithmetic(39617)

Question 1141508: a company manufactures and sells bar stools. Manufacturing costs consist of a fixed cost of R25000 a month and a variable cost of R350 per unit. each unit is sold at R600.
1. Determine the linear profit equation
2. What is the break even level
3. Draw a neat graph showing profit as a function of the number of units sold.
Click here to see answer by josmiceli(19441)

Question 1141754: The value of a gold coin picturing the head of the Roman Emperor Domitian is increasing at the rate of 7% per year. If the coin is worth $105 now, what will it be worth in 11 years?

Click here to see answer by josmiceli(19441)

Question 1141755: Ina Crespo rowed 13.5 miles down the Habashabee River in 1.5 hours, but the return trip took her 4.5 hours. Find the rate Ina rows in still water and the rate of the current. Let x represent the rate Ina can row in still water and let y represent the rate of the current.

Click here to see answer by ikleyn(52786)

Question 1141834: Hello,
Can you show me how to solve the following using elimination method or the substitution method?
1. 8x+5y= 180.50
2. 12x+6y= 261.00

Click here to see answer by josmiceli(19441)

Question 1141850: A product may be made using Machine I or Machine II. The manufacturer estimates that the monthly fixed costs of using Machine I are $19,000, whereas the monthly fixed costs of using Machine II are $15,000. The variable costs of manufacturing 1 unit of the product using Machine I and Machine II are $13 and $19, respectively. The product sells for $60 each.
(a) Find the cost functions C(x) associated with using each machine, where x is the number of units produced using that machine.
Machine I C1(x) =

Machine II C2(x) =

(b) Sketch the graphs of the cost functions of part (a) and the revenue function on the same set of axes. (Sketch the graphs using rays.)
(c) Which machine should management choose to maximize their profit if the projected sales are 450 units?
Machine I
Machine II
Which machine should management choose to maximize their profit if the projected sales are 550 units?
Machine I
Machine II
Which machine should management choose to maximize their profit if the projected sales are 650 units?
Machine I
Machine II
(d) What is the profit for each case in part (c)?
450 units $
550 units $
650 units $
Click here to see answer by Theo(13342)

Question 1141859: The total value of quarters and dimes in a coin bank is $6.90. If the quarters were dimes and the dimes were quarters, the total value of the coins would be $7.80.
a) set up a system if equations to represent the situation.
b) find the number of quarters in the bank.
please give details, thankyou
Click here to see answer by josgarithmetic(39617)

Question 1141874: In a certain state, the sales tax T on the amount of taxable goods is 8% of the value of the goods purchased (x), where both T and x are measured in dollars.
(a) Express T as a function of x.
T(x) =

(b) Find T(250) and T(4.80). (Round your answers to two decimal places.)
T(250) =
T(4.80) =

Click here to see answer by Theo(13342)

Question 1141984: substitutions method: a - 3 = 4b; 2a + 4b =9

Click here to see answer by Boreal(15235)

Question 1142109: Five more than three times a number is 197. Find the number.
Click here to see answer by Alan3354(69443)

Question 1142119: What is an equation of the line that passes through the point (−4,−3) and is perpendicular to the line 2x+3y=152x+3y=15?
Click here to see answer by Alan3354(69443)

Question 1142239: Solve the following system of equations by graphing. If the system is inconsistent or the equations are dependent, say so. 7x-5y=2, 14x-10y=4
Click here to see answer by ikleyn(52786)

Question 1142240: Solve the following system of equations by graphing.
x-2y=8, x+2y=-4

then write the ordered pair, or the infinitely number and if dependent number of solutions
Click here to see answer by josgarithmetic(39617)

Question 1142256: Write the point-slope form of the equation of the line satisfying the given conditions. Then use the point-slope form of the equation to write the slope-intercept form of the equation. x-intercept= -1/2 y-intercept=2
Click here to see answer by josgarithmetic(39617)

Question 1142350: How many students have used three mode of transportation

Click here to see answer by Alan3354(69443)

Question 1142729: Hello,I'd like help on this question
Factor f(x)=4x^3+11x^2-40x+25 into linear factors given that −5 is a zero of f(x).
Thank you
Click here to see answer by josgarithmetic(39617)

Question 1142882: 5x + 5y - 4z = 13
5x + 3y + z = - 3
3x - 2y - z = - 10
x=___
y=___
z=___
solve the system
Click here to see answer by Alan3354(69443)

Question 1142940: Select all the statements that are true for the following systems of equations.
System A System B System C
2x - 3y = 4 3x - 4y = 5 2x - 3y = 4
4x - y = 18 y = 5x + 3 12x - 3y = 54
Click here to see answer by solver91311(24713)

Question 1142963: The product of two consecutive odd integers is 1023. Find the sum of the two integers.
Click here to see answer by solver91311(24713)

Question 1142963: The product of two consecutive odd integers is 1023. Find the sum of the two integers.
Click here to see answer by Alan3354(69443)

Question 1142962: Five less than six times the largest of three consecutive positive integers is equal to the square of the smallest integer minus two times the middle integer. Find the largest integer.
Click here to see answer by josgarithmetic(39617)

Question 1142960: The sum of two numbers is 21. Find the difference between the two numbers if one number is 3 less than the other
Click here to see answer by Alan3354(69443)

Question 1142961: A number is 1 more than twice another. Their squares differ by 176. What is the smaller number?
Click here to see answer by ikleyn(52786)

Question 1142961: A number is 1 more than twice another. Their squares differ by 176. What is the smaller number?
Click here to see answer by MathTherapy(10552)

Question 1142958: Given three consecutive even integers. Find the largest integer if the second plus twice the third is 4 times the first

Click here to see answer by ikleyn(52786)

Question 1142959: Given three consecutive even integers. Find the largest integer if the second plus twice the third is 4 times the first.
Click here to see answer by ikleyn(52786)

Question 1143048: I am trying to determine the value of "x" from the following problem:
"This linear equation; What function of f(x) when x = 0"?
(x) f(x)
2 30
9 16
x 10
I tried drawing a graph, but it was not linear because I thought x was 3, since it is 1/2 the difference of 16 and 10. (The pattern is the same for the previous numbers).
Click here to see answer by josmiceli(19441)

Question 1143266: Use Cramers rule to solve the system of equations that follow
3x + 2y + z = 5, 2x + 3y + z = 1, 2x + y + 3z = 11.
[
Click here to see answer by Edwin McCravy(20056)

Question 1143329: How do I find the following? The line passing through the points (-5,-2) and (-2,-1) has equation?
Click here to see answer by josgarithmetic(39617)

Question 1143329: How do I find the following? The line passing through the points (-5,-2) and (-2,-1) has equation?
Click here to see answer by Alan3354(69443)

Question 1143520: Hello! I need help with this equation.
Find a value for a so that the solution of the system is (6, - 1)
y = 2/3x - 5
y = ax + 5
Thanks!
Click here to see answer by ikleyn(52786)

Older solutions: 1..45, 46..90, 91..135, 136..180, 181..225, 226..270, 271..315, 316..360, 361..405, 406..450, 451..495, 496..540, 541..585, 586..630, 631..675, 676..720, 721..765, 766..810, 811..855, 856..900, 901..945, 946..990, 991..1035, 1036..1080, 1081..1125, 1126..1170, 1171..1215, 1216..1260, 1261..1305, 1306..1350, 1351..1395, 1396..1440, 1441..1485, 1486..1530, 1531..1575, 1576..1620, 1621..1665, 1666..1710, 1711..1755, 1756..1800, 1801..1845, 1846..1890, 1891..1935, 1936..1980, 1981..2025, 2026..2070, 2071..2115, 2116..2160, 2161..2205, 2206..2250, 2251..2295, 2296..2340, 2341..2385, 2386..2430, 2431..2475, 2476..2520, 2521..2565, 2566..2610, 2611..2655, 2656..2700, 2701..2745, 2746..2790, 2791..2835, 2836..2880, 2881..2925, 2926..2970, 2971..3015, 3016..3060, 3061..3105, 3106..3150, 3151..3195, 3196..3240, 3241..3285, 3286..3330, 3331..3375, 3376..3420, 3421..3465, 3466..3510, 3511..3555, 3556..3600, 3601..3645, 3646..3690, 3691..3735, 3736..3780, 3781..3825, 3826..3870, 3871..3915, 3916..3960, 3961..4005, 4006..4050, 4051..4095, 4096..4140, 4141..4185, 4186..4230, 4231..4275, 4276..4320, 4321..4365, 4366..4410, 4411..4455, 4456..4500, 4501..4545, 4546..4590, 4591..4635, 4636..4680, 4681..4725, 4726..4770, 4771..4815, 4816..4860, 4861..4905, 4906..4950, 4951..4995, 4996..5040, 5041..5085, 5086..5130, 5131..5175, 5176..5220, 5221..5265, 5266..5310, 5311..5355, 5356..5400, 5401..5445, 5446..5490, 5491..5535, 5536..5580, 5581..5625, 5626..5670, 5671..5715, 5716..5760, 5761..5805, 5806..5850, 5851..5895, 5896..5940, 5941..5985, 5986..6030, 6031..6075, 6076..6120, 6121..6165, 6166..6210, 6211..6255, 6256..6300, 6301..6345, 6346..6390, 6391..6435, 6436..6480, 6481..6525, 6526..6570, 6571..6615, 6616..6660, 6661..6705, 6706..6750, 6751..6795, 6796..6840, 6841..6885, 6886..6930, 6931..6975, 6976..7020, 7021..7065, 7066..7110, 7111..7155, 7156..7200, 7201..7245, 7246..7290, 7291..7335, 7336..7380, 7381..7425, 7426..7470, 7471..7515, 7516..7560, 7561..7605, 7606..7650, 7651..7695, 7696..7740, 7741..7785, 7786..7830, 7831..7875, 7876..7920, 7921..7965, 7966..8010, 8011..8055, 8056..8100, 8101..8145, 8146..8190, 8191..8235, 8236..8280, 8281..8325, 8326..8370, 8371..8415, 8416..8460, 8461..8505, 8506..8550, 8551..8595, 8596..8640, 8641..8685, 8686..8730, 8731..8775, 8776..8820, 8821..8865, 8866..8910, 8911..8955, 8956..9000, 9001..9045, 9046..9090, 9091..9135, 9136..9180, 9181..9225, 9226..9270, 9271..9315, 9316..9360, 9361..9405, 9406..9450, 9451..9495, 9496..9540, 9541..9585, 9586..9630, 9631..9675, 9676..9720, 9721..9765, 9766..9810, 9811..9855, 9856..9900, 9901..9945, 9946..9990, 9991..10035, 10036..10080, 10081..10125, 10126..10170, 10171..10215, 10216..10260, 10261..10305, 10306..10350, 10351..10395, 10396..10440, 10441..10485, 10486..10530, 10531..10575, 10576..10620, 10621..10665, 10666..10710, 10711..10755, 10756..10800, 10801..10845, 10846..10890, 10891..10935, 10936..10980, 10981..11025, 11026..11070, 11071..11115, 11116..11160, 11161..11205, 11206..11250, 11251..11295, 11296..11340, 11341..11385, 11386..11430, 11431..11475, 11476..11520, 11521..11565, 11566..11610, 11611..11655, 11656..11700, 11701..11745, 11746..11790, 11791..11835, 11836..11880, 11881..11925, 11926..11970, 11971..12015, 12016..12060, 12061..12105, 12106..12150, 12151..12195, 12196..12240, 12241..12285, 12286..12330, 12331..12375, 12376..12420, 12421..12465, 12466..12510, 12511..12555, 12556..12600, 12601..12645, 12646..12690, 12691..12735, 12736..12780, 12781..12825, 12826..12870, 12871..12915, 12916..12960, 12961..13005, 13006..13050, 13051..13095, 13096..13140, 13141..13185, 13186..13230, 13231..13275, 13276..13320, 13321..13365, 13366..13410, 13411..13455, 13456..13500, 13501..13545, 13546..13590, 13591..13635, 13636..13680, 13681..13725, 13726..13770, 13771..13815, 13816..13860, 13861..13905, 13906..13950, 13951..13995, 13996..14040, 14041..14085, 14086..14130, 14131..14175, 14176..14220, 14221..14265, 14266..14310, 14311..14355, 14356..14400, 14401..14445, 14446..14490, 14491..14535, 14536..14580, 14581..14625, 14626..14670, 14671..14715, 14716..14760, 14761..14805, 14806..14850, 14851..14895, 14896..14940, 14941..14985, 14986..15030, 15031..15075, 15076..15120, 15121..15165, 15166..15210, 15211..15255, 15256..15300, 15301..15345, 15346..15390, 15391..15435, 15436..15480, 15481..15525, 15526..15570, 15571..15615, 15616..15660, 15661..15705, 15706..15750, 15751..15795, 15796..15840, 15841..15885, 15886..15930, 15931..15975, 15976..16020, 16021..16065, 16066..16110, 16111..16155, 16156..16200, 16201..16245, 16246..16290, 16291..16335, 16336..16380, 16381..16425, 16426..16470, 16471..16515