Lana has $90. She spends 70% of the money. She then invests the remaining amount and earns a profit of 60%. How much money does she now have?

Correlation of two variables falls into:

Positive correlation: an increase in one variable causes another variable to increase

Negative correlation: an increase in one variable causes another one to decrease

No correlation: a change in one variable does not cause any response in another variable.

From the given choices

Option a is no correlation

Option b is a no correlation

Option c is a negative correlation

Option d is a positive correlation

To form an equation from the word problem, first break the given statement into smaller statements.

First, we are given the width of the rectangle as x. We are told, the length is three times width. Mathematically, this means

Length=3*width=3*x=3x

Again, the length is 4 less than 3 times width of the rectangle. Thus, the length of rectangle in terms of width becomes:

Length =3x-4

This is the required equation.

In the given problem, we use the calculator to evaluate the product 1.9 * 0.75 = 1.425

to find the average time the athlete runs in 1 mile; we find total distance and total time the athlete takes in running.

Total distance run by athlete=7+3=10 miles

Total time=45+15 =60 minutes

The athlete runs 10 miles in 60 minutes. For the athlete to cover 1 mile, he will run for a time less than 60 minutes. Thus, in 1 mile, the athlete takes:

So, in 6 minutes, the athlete covers 1 mile.

In this problem, we need to find the amount of gratuity the couple will leave. The gratuity is 16% of the total bill. Before solving the problem, the following are terms and their meaning in percent problems:

• Is means equals
• Of means multiply
• What means unknown (variable)

If we let x be the amount of gratuity, then translating the given problem into a mathematical equation becomes:

Now we evaluate the above equation noting that of means multiply.

So, the value of x=9.376 and to the nearest cent, x=9.38

There, a couple will leave a gratuity of $9.38.

Here we convert between feet and yards. We know 1 yard =3 feet. Then, 27 feet to yards will be:

Thus, 9 yards is equal to 27 ft.

The median of a data set is found in two ways:

For an odd data set, the median fall in the (N+1)/2 th position.

For an even data set, the median is the average of the element in the (N/2)th and (N+1)/2 th positions.

To find the median of the given data set, we need to arrange the elements from the smallest to the largest as follows:

12, 12, 16, 18, 19, 22, 23, 24, 26, 35, 35

There are 11 elements in the data set. 11 is an odd number and the median fall in the (N+1)/2 th position.

Median =(11+1)/2=12/2=6 th position.

From the organized data, the element in the 6th position is 22, which is the required median for the data set.

In order for the teacher to better visualize the test performance for his class, he needs to present the mark distribution in chart form. A better chart visualizer is the histogram, which will show the frequency of marks against range of test scores. A bar graph will not be used because the rectangles need to touch one another.

In a bar graph, the rectangles do not touch each other. Therefore, it will not be a good chart visualizer.

We use given information to find how much ammonia is need to make the specified solution.

We are told, one gallon of cleaning solution requires 10oz of ammonia. Expressing this mathematically yields two options:

\(\frac{10\ oz\ of\ ammonia}{1\ gallon\ of\ solution}\)or\(\frac{1\ gallon\ of\ solution}{10\ oz\ of\ ammonia}\)

Now we find how much ammonia is needed using option two.

\(51\ gallon\ of\ solution\ *\frac{10\ oz\ of\ ammonia}{1\ gallon\ of\ solution}\ =\ 510\ oz\ of\ ammonia\)

From the above equation, gallon of solution will cancel, and oz of ammonia is left.

Therefore, the solution will require 510 oz of ammonia.

Before finding the area of the pizza, we need to find the radius of the pizza.

Find radius of the pizza in terms of diameter

Next, find area of the pizza using the radius of 6 inches

Substituting r=6 in the equation of the area of a circle

Thus, the pizza has an area of 36 π in2.