Math Questions

John is twice as old as Mary. The sum of their ages is 21. How old is Mary? Let J = John's age and M = Mary's age. Select the system equations that represents the problem. J-2M=0 J-M=2 M-2J=0 J+M=21

Solve by factoring: 3x^2 + 7x + 2 = 0 x =1/3 orx = 2 x = -1/3 or x = 2 x=1/3 orx = -2 x= -1/3 or x = -2

Factor: 10x2-x-2 (2x - 1) (5x + 2) (2x + 1) (5x - 2) (2x - 1) (5x-2) (2x + 1) (5x + 2)

You want to know what freshman think of their science class. You poll 100 freshman by using a random number generator to pick students by their student number. Random Non-random

A driver gear is turning at 450 rpm and has 130 teeth. If the driven gear needs to turn at 914 rpm, how many teeth should the driven gear have? 103 teeth 64 teeth 87 teeth 502 teeth

The mean height of women in a country (ages 20-29) is 64.2 inches. A random sample of 65 women in this age group is selected. What is the probability that the mean height for the sample is greater than 65 inches? Assume σ = 2.96.

Classify this survey: You are interested in the number of students that would be interested in attending a Dance Marathon to benefit Riley Children's Hospital. You survey everyone in their first period class. Random Non-random

You survey customers at a mall. You want to know which stores they shop at the most. You walk around a computer shop and choose 20 customers there for your survey. Non-random Random

A football is punted into the air. Its height is given by h(t) = -4.9t² +24.5t +1 where h is in meters and t is in seconds Find the maximum height of the ball and the time the ball reaches its maximum height

The population mean and standard deviation are given below. Find the required probability and determine whether the given sample mean would be considered unusual. For a sample of n = 70, find the probability of a sample mean being less than 22.1 if u = 22 and σ = 1.31. For a sample of n = 70, the probability of a sample mean being less than 22.1 if µ = 22 and σ=1.31 is ___ (Round to four decimal places as needed.). Would the given sample mean be considered unusual? The sample mean___be considered unusual because it has a probability that is than 5%.

In an experiment which group receives no special instructions? the independent group the control group the treatment group the biggest group

The amount of money Stephanie collected in tips in each of seven days is $46, $82, $103, $27, $54, $71, and $65. Determine the mean, median, mode, and midrange.

What are the x-intercepts of the function f (x) = 2x² + 7x-4? x=-1/2₁x = 4 x = 1/2, x=-4 x=-8, x = 1 x=4,x=-7

Use factoring to solve: 7x² + 8x + 1 = 0 x = -7 or x = 1/7 x = 1 or x = 1/7 x = -1 or x = -1/7 x = -1 or x = 1/7

Justin has 3 skateboards and plans to purchase 2 more skateboards each month. Does this situation model a linear or exponential function? Exponential Linear

Find the probability and interpret the results. If convenient, use technology to find the probability. The population mean annual salary for environmental compliance specialists is about $62,000. A random sample of 36 specialists is drawn from this population. What is the probability that the mean salary of the sample is less than $58,500? Assume σ = $6,500. The probability that the mean salary of the sample is less than $58,500 is 0.00062. (Round to four decimal places as needed.) Interpret the results. Choose the correct answer below. A. About 0.06% of samples of 36 specialists will have a mean salary less than $58,500. This is not an unusual event. B. Only 6% of samples of 36 specialists will have a mean salary less than $58,500. This is an extremely unusual event. C. Only 0.06% of samples of 36 specialists will have a mean salary less than $58,500. This is an extremely unusual event. D. About 6% of samples of 36 specialists will have a mean salary less than $58,500. This is not an unusual event.

A manufacturer determines that the number of drills it can sell is given by the formula D = -4p² + 160p - 305 where p is the price of drills in dollars. At what price will the manufacturer sell the maximum number of drills? a) $22 b) $20 c) $40 d) $80

Find the missing value "c" to create a perfect square trinomial for x² + 16x + c 64 4 -4 08

A 20% acid solution is mixed with a 70% acid solution to get 50 liters of a 40% solution. Which of the following expressions is equal to 4(50)? 2x+7y 0.2x-0.7y x+y

Knowledge: 1. A coin is tossed three times. What is the best description of the tree diagram that illustrates this event? A 2 stages, 3 branches per stage, 6 outcomes B 3 stages, 2 branches per stage, 8 outcomes C 2 stages, 3 branches per stage, 9 outcomes D 3 stages, 2 branches per stage, 6 outcomes 2. Cameron is forming a password containing 3 characters. He has decided that the first character will be a capital letter and the last character will be a digit. All other characters will be lower case letters. How many unique passwords could Cameron form? A 39 B 780 C 4056000 D 6760 D 6760

Choose the best answer for each question. Round answers to two decimal places. If to use pi, use 3.14 unless otherwise stated. Write an equation of a circle centered at the origin with a radius of 5. x² + y² = -25 x² + y² = 5 x² + y² = 10 x² + y² = 25 None of the other answers

What are the x-intercepts of the function f (x) = (x − 9) (x - 7)? x = -9, x = -7 x = 9,x=7 x = -9, x = 7 x = 9, x=-7

The areas of two similar rectangles are 1000 ft² and 360 ft². Compare the larger rectangle to the smaller rectangle. Find the ratio of their perimeters. A. 3:5 B. 25:9 C. 50:18 D. 5:3

What is the resulting equation when the expression for y in the second equation is substituted into the first equation? 3x+y=1 y = 6-4x 7x+6=1 x+61 x+6-1

Which method is not used to find the solution of a system of linear equations. substitution guess and check graphing matrices

Write the equation in its equivalent exponential form. Then solve for x. log 4(x-4) = 2 log 4(x-4) = 2 in its equivalent exponential form is. (Do not simplify.) x=

a square root function that has been vertically stretched by a factor of 4, reflected in the y-axis, horizontally stretched by a factor of 2, and translated 3 units left and 5 units up.

What point of concurrency in a triangle is always located inside the triangle? A. orthocenter, only B. Incenter, only C. orthocenter and circumcenter D. centroid and incenter

When transforming any function the rule f(x +3) tells us to move the function left three units. False True

A rocket is launched at the top of a building. The height of the rocket (in meters) written in terms of time (seconds) can be modeled by h (1) = -4.912 +9.8t + 73.5. What is the maximum height? 73.5 meters 80 meters 78.4 meters 9.8 meters

Use the appropriate compound interest formula to compute the balance in the account after the stated period of time $16,000 is invested for 5 years with an APR of 2% and daily compounding. The balance in the account after 5 years is $ (Round to the nearest cent as needed.)

The areas of two similar rectangles are 1000 ft² and 360 ft². Compare the larger rectangle to the smaller rectangle. Find the ratio of their perimeters. A. 3:5 B. 25:9 C. 50:18 D. 5:3

If the zeros of a quadratic equation are -3 and 5, what would be the x-intercepts? (3, 0) and (5, 0) (-3,0) and (-5, 0) (3, 0) and (-5, 0) (-3,0) and (5, 0)

What is a sample obtained by using chance methods? Every member of the population has an equal chance of being selected. biased none of the answer choices random systematic

Identify the study as observational, experimental, or neither. A professor finds that people who are overweight have higher cholesterol levels than those that are not overweight. experimental observational neither answer choice

Directions - Find the x and y-intercepts from the Standard Form equation. Write your answers as ordered pairs. -5x - 2y = 10 x-intercept = ( y-intercept = (

Classify the following: A person's salary and the amount of money saved. No correlation Correlation that implies causation Correlation only

Sketch the graph of the inequality. 3x - 4y < 12 Step 1 To graph the given inequality, first replace the inequality symbol by an equality sign. 3x - 4y = 12 Graph the equation using a dashed line, as the solution set does not contain the boundary

The length of a rectangle is 4 inches more than its width, and its perimeter is 34 inches. Find the length and width of the rectangle. Find the width of the rectangle. 7.5 in 6.5 in 6 in

The mean height of women in a country (ages 20-29) is 63.9 inches. A random sample of 75 women in this age group is selected. What is the probability that the mean height for the sample is greater than 64 inches? Assume σ = 2.69. The probability that the mean height for the sample is greater than 64 inches is.

Identify the study as observational or experimental. One group of subjects was given an herbal supplement for one year, another group was given a placebo. After one year, the number of illnesses each group had was compared.

In a hydraulic system, an input piston has an area of 22.0 in² and an output piston with an area 70.6 in². A weight or resistance of 150 pounds is on the output piston. What is the pressure? 2.12 psi 5,261 psi 792.3 psi 1,445 psi

Directions - Convert the following equation to Standard Form. Make sure the leading coefficient is positive, and all integers are whole numbers. 2y = -3x+5 Standard Form:

On a second class lever, a 12 lb input force (effort force) is 30 inches from the fulcrum. Where should a 34 lb load (resistance force) be placed so it can be lifted? 5.00 in 27.4 in 10.6 in 83.9 in

Is there a correlation between the salary of a teacher and their shoe size? no correlation correlation correlation that implies causation

Rosa invests $3300 in an account with an APR of 3% and annual compounding. Julian invests $2800 in an account with an APR of 4% and annual compounding. Complete parts a through c. a. Compute the balance in each account after 5 and 20 years. After 5 years Rosa will have a balance of approximately $___After 20 years Rosa will have a balance of approximately $. (Round to the nearest cent as needed.)

Classify the following: The number letters in a city and the population of the city. Correlation only No correlation Correlation that implies causation

...... is a sample used by chance methods in statistics. Every member of the population has the same chance of being selected. control biased random independent

f(x)=x²-16x +60 (Type an ordered pair, using integers or fractions.) (b) Find an equation for the axis of symmetry. x=8 (Type an equation. Use integers or fractions for any numbers in the equation.) (c) Determine whether the parabola has a maximum or a minimum and find its value. Select the correct choice below and fill in the answer box within your choice. (Type an integer or a fraction.) A. The parabola opens upward and has a minimum value of B. The parabola opens downward and has a maximum value of

Use the sequence to answer the following. 0, 2, 4, 6,....... The sequence shown is___and uses a common___which is___ The next three (3) terms would be___,____, and___ Use the sequence to find the following. a(1) = a(15) =