A class of 40 students has 18 boys and 22 girls. What is ratio of girls to boys in the class?

We need to find the amount Lana left after spending and investing another.

Lana spends=70% of $90=70/100 * 90 = $63

Amount left after spending=$(90-63) = $27

Lana is left with $27, which she will invest and earns a profit of 60%.

Profit earned=60% of $27 = 60/100 * 27 = $16.20

Therefore, Lana will have $27 + $16.20 = $43.20

Scatter plots can depict three correlations: positive, negative and no correlation. A positive correlation scatter plot reveals that as one variable increases, the other variable also increases as shown below

To change between L and mL, the following two options are used.

The truck carries a whole cargo which equals 1. If we let the weight of the cargo to be p, then we set up a proportion equation with weight as numerator and fraction of cargo as denominator.

Solve for value of p by cross products

Multiply both sides by 3/2 a reciprocal of 2/3

The truck carries a cargo weighing 795 lb.

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.

From the given data, we can draw the following triangle by letting the unknown length to be p.

We apply the Pythagoras theorem, the value of p:

The unknown length of the triangle is about 21.4 feet.

We use 1 L =1000 mL to convert between the two units. The conversion options of interconversions are:

And

We want millimeters, use the second option to change L to mL as:

Therefore, 2.5 L is equivalent to 2500 mL.

An independent variable is a change that when modified brings a change in other variables. In this case, the person increases his climbing rate, calories burned, distance traveled and energy used increases. Therefore, the walking speed is the independent variable while other variables are dependent.

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

The selling price of the sweater is marked price less the mark off value.

Mark off value=mark off rate*original price

Mark of value=30% of $95

Mark of value=0.30*$95=$28.50

Now, find the selling price of the sweater

Selling price= marked price-mark off value

Thus, the sweater will be sold for 66.50 after applying a mark off of 30%. The selling price is about $67.