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Question 1136653: A scientist needs 150 milliliters of a 20% acid solution for an experiment. The lab has available a 25% and a 10% solution. How many milliliters of the 25% solution and how many milliliters of the 10% solution should the scientist mix to make the 20% solution?
Click here to see answer by josgarithmetic(39616)

Question 1136823: The length of a rectangle is three more than twice its width if the area of the rectangle is 44cm2 what is the perimeter
Click here to see answer by josgarithmetic(39616)

Question 1136872: The perimeter of a triangle is 83 inches. The longest side is three times the length of the shortest side and 17 inches more than half the sum of the other two sides. Find the length of all three sides using a system of equations.
Click here to see answer by ikleyn(52776)

Question 1136887: Mark is increasing his exercise routine by running and walking at least 5 miles each day. His goal is to burn a minimum of 700 calories from this exercise. Walking burns 110 calories/mile and running burns 210 calories. Write a system of inequalities to model this situation. Let r represent the number of miles Mark runs and let w represent the number of miles Mark walks.
Click here to see answer by ikleyn(52776)

Question 1136886: Juan is studying for his final exams in Chemistry and Algebra. He knows he only has 24 hours to study, and it will take him at least two times as long to study for Algebra than Chemistry. Write a system of inequalities to model this situation. Let a represent the number of hours spent studying for Algebra and let c represent the number of hours spent studying for Chemistry.
Click here to see answer by ikleyn(52776)

Question 1136879: I don't know if this is the right section here's the problem I need help with

Consider the following two independent random variables,
X
and
Y
.
Random variable
X
has a mean of 18 and a standard deviation 9.
Random variable
Y
has a mean of 24 and a standard deviation 4.
Find the mean, variance, and standard deviation for the following linear combinations of
X
and
Y
.

Click here to see answer by MathLover1(20849)

Question 1136885: Caitlyn sells her drawings at the county fair. She wants to sell at least 70 drawings and has portraits and landscapes. She sells the portraits for $15 and the landscapes for $10. She needs to sell at least $800 worth of drawings in order to earn a profit. Write a system of inequalities to model this situation. Let p represent the number of portraits sold and let l represent the number of landscapes sold.
Click here to see answer by ikleyn(52776)

Question 1136890: Zeros of Functions
Find an nth degree polynomial function with real coefficients such that:
n=3
1 and i are zeros
f(-1)=8
Click here to see answer by Alan3354(69443)

Question 1136972: The sum of the measures of the angles of a triangle is 180. The sum of the measures of the second and third angles is twice the measure of the first angle. The third angle is eighteen more than the second. Find the measures (in degrees) of the three angles.
Click here to see answer by josgarithmetic(39616)

Question 1136971: The sum of the measures of the angles of a triangle is 180. The sum of the measures of the second and third angles is three times the measure of the first angle. The third angle is fifteen more than the second. Find the measures (in degrees) of the three angles.
Click here to see answer by josgarithmetic(39616)

Question 1136974: The church youth group is selling snacks to raise money to attend their convention. Amy sold 2 pounds of candy, 3 boxes of cookies, and 1 can of popcorn for a total sales of $55. Brian sold 4 pounds of candy, 6 boxes of cookies, and 3 cans of popcorn for a total sales of $120. Paulina sold 8 pounds of candy, 8 boxes of cookies, and 5 cans of popcorn for a total sales of $210. What is the cost of each item?
Click here to see answer by josgarithmetic(39616)

Question 1136979: After watching a major musical production at the theater, the patrons can purchase souvenirs. If a family purchases 6 t-shirts, the video, and a stuffed animal, their total is $135.
A couple buys 2 t-shirts, the video, and 5 stuffed animals for their nieces and spends $175. Another couple buys 2 t-shirts, the video, and a stuffed animal, and their total is $75. What is the cost of each item?
Click here to see answer by greenestamps(13198)

Question 1136973: After watching a major musical production at the theater, the patrons can purchase souvenirs. If a family purchases 6 t-shirts, the video, and a stuffed animal, their total is $135.
A couple buys 2 t-shirts, the video, and 5 stuffed animals for their nieces and spends $175. Another couple buys 2 t-shirts, the video, and a stuffed animal, and their total is $75. What is the cost of each item?
Click here to see answer by ankor@dixie-net.com(22740)

Question 1137061: The graph of a linear function intersects with the x axis at a point with an abscissa of 4 and with the y axis at a point with an ordinate of 11. Write the formula of the function.
Click here to see answer by Alan3354(69443)

Question 1137077: Sharyn invests 2000 more in an account that earns 9% simple interest than she invests in an account that earns 6% simple interest. How much did she invest in each account if her total interest is $405 after 1 year?
Click here to see answer by Boreal(15235)

Question 1137088: Dave earned the following test scores in his
biology class: 82, 88, 92, and 93. How high does he have to score on the fifth test to have an average of 90 or more?
Click here to see answer by ikleyn(52776)

Question 1137089: The product of and the sum of a number and 3
is between - 1 and 5. Find all such numbers.
Click here to see answer by ikleyn(52776)

Question 1137087: The length of a rectangle is 2 ft more than the
width. Find the dimensions if the perimeter is 40 ft
Click here to see answer by ikleyn(52776)

Question 1137085: How much 10% acid solution should be mixed
with 1 L of 25% acid solution to produce a solution that is 15% acid?
Click here to see answer by ikleyn(52776)

Question 1137085: How much 10% acid solution should be mixed
with 1 L of 25% acid solution to produce a solution that is 15% acid?
Click here to see answer by Alan3354(69443)

Question 1137097: A school carnival sold tickets to ride on a
Ferris wheel. The charge was $1.50 for adults and $1.00 for students. If 54 tickets were sold for a total of $70.50, how many of each type of ticket were sold?
Click here to see answer by josgarithmetic(39616)

Question 1137096: Melinda invested twice as much money in an
account paying 5% simple interest as she did in an account paying 3.5% simple interest. If her total interest at the end of 1 yr is $303.75, find the amount she invested in the 5% account.
Click here to see answer by ikleyn(52776)

Question 1137092: One method to approximate your maximum
heart rate is to subtract your age from 220. To maintain an aerobic workout, it is recommended that you sustain a heart rate of between 60% and 75% of your maximum heart rate. a. If the maximum heart rate h is given by the
formula h = 220 - A, where A is a person's age, find your own maximum heart rate. (Answers will vary.)
Click here to see answer by Alan3354(69443)

Question 1137086: Two friends plan to meet at a restaurant for
lunch. They both leave their homes at 11:30 A.M. and between the two of them, they drive a total of 37.5 mi. Lynn drives in from a neighboring town and averages 15 mph faster than her friend Linda. If they meet at noon, find the average driving speed for each.
Click here to see answer by VFBundy(438)

Question 1137459: Hello awesome tutors, this is a variation problem. I could not find a category to match this problem and I hope that someone can help me work this out and solve. I don't understand what the book is telling me to do. Thank you in advance.
T varies jointly as r and B squared. When r=7 and B=6,
T=1008. Find T when r is 10 and B is 12.
Click here to see answer by josgarithmetic(39616)

Question 1137795: Solve the following system of linear equations using any algebraic method. If possible, check your solution.
8 - 6y =12
12x - 9y = 18
I solved all problems except this one. Could someone help me?
Click here to see answer by rothauserc(4718)

Question 1137839: Find the solution(s) of each system of equations.
y=x^2+6x+9
y=3x
Click here to see answer by ikleyn(52776)

Question 1137841: Find the solution(s) of each system of equations.
y=x^2+8x+30
y=5-2x
Click here to see answer by MathLover1(20849)

Question 1138822: A pennant is shaped like a right triangle, with hypotenuse 15 feet. The length of one side of the pennant is three feet longer than the length of the other side. Find the length, in feet, of the two sides of the pennant.
Click here to see answer by greenestamps(13198)

Question 1138821: A goat enclosure is in the shape of a right triangle. One leg of the enclosure is built against the side of the barn. The other leg is 4 feet more than the leg against the barn. The hypotenuse is 8 feet more than the leg along the barn. Find the length, in feet, of the three sides of the goat enclosure.
Click here to see answer by ikleyn(52776)

Question 1138820: Juli is going to launch a model rocket in her back yard. When she launches the rocket, the function
h(t) = −16t2 + 32t
models the height, h, of the rocket above the ground as a function of time, t.
(b)
Find the time (in seconds) the rocket will be 16 feet above the ground.
Click here to see answer by josmiceli(19441)

Question 1138973: please explaing.
Write a slope-intercept equation for a line that passes through (8, 6) and (-6, 6).
Click here to see answer by MathLover1(20849)

Question 1139134: The sum of two numbers is 59
and the difference is 9
. What are the numbers?
Click here to see answer by rothauserc(4718)

Question 1139396: 2 % is equivalent to what fraction in reduced terms?
Click here to see answer by josgarithmetic(39616)

Question 1139396: 2 % is equivalent to what fraction in reduced terms?
Click here to see answer by Theo(13342)

Question 1139398: Chris flies a plane against a headwind for 4560 miles. The return trip with the wind took 16 hours less time. If the wind speed is 8 mph, how fast does Chris fly the plane when there is no wind?
Click here to see answer by josgarithmetic(39616)

Question 1139395: Find the unit price. If necessary, round your answer to the nearest cent. You would enter an answer like $0.49/pound, the value (like 0.49) in the first box and the appropriate unit (like pound) in the second box.
8 pints for $3.89
Click here to see answer by Theo(13342)

Question 1139397: Matt invests $9600 in two different accounts. The first account paid 5 %, the second account paid 4 % in interest. At the end of the first year he had earned $428 in interest. How much was in each account?

Click here to see answer by josgarithmetic(39616)

Question 1139394: Savannah needs to rent a car while on vacation. The rental company charges $17.95, plus 19 cents for each mile driven. If Savannah only has $40 to spend on the car rental, what is the maximum number of miles she can drive?

Click here to see answer by algebrahouse.com(1659)

Question 1139572: please explain how to solve for x:
x - 2√x - 24 = 0
Click here to see answer by Alan3354(69443)

Question 1139573: please explain:
Determine whether there is a maximum or minimum value for f(x) = -2x^2 + 3x + 4 and find that value
Click here to see answer by Alan3354(69443)

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