A farmer is planning for a growing season and want to know the trend in amount of rainfall in his area. He obtains rainfall falling in the first 5 months of the year as shown in the above table. Which of the following would best display the data?

Month	January	February	March	April	May
Rainfall (mm)	20	6	14	28	34

 

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.

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

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.

We solve for the value of x by following the order of operations

3(x-2)=15

Divide both sides of the equation by 3

Add 2 to both sides of the equation

Thus, the value of x is 8.

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.

Based rainfall falling for the first 5 months, a bar graph will give a great display for the farmer to decide when start planting. The horizontal scale will represent months of the year and vertical scale will present the amount of rainfall falling.

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.

From the cost of 45 syringes, we are required to find the cost of 5 syringes. We set up a proportion equation by letting the cost of 5 syringes to y. Besides, we let the cost to be numerator and number of syringes to be denominator as follows.

Solve the value of y by cross products

Divide both sides by 45

Therefore, 5 syringes will cost $80.00.

We are asked to find mL equivalent in 1.5 teaspoons. To carry out the operations, we utilize dimensional analysis to solve this problem as follows.

Converting between teaspoon and mL uses the following conversions:

Or

Since we want to remain with mL, use the second option and proceed as follows.

Thus, 1.5 teaspoons is equal to 7.395 mL

A ratio is of the form a : b but can also be converted to a fraction of the form a/b, where b is not equal to zero. Besides, to in ration means per in fraction form.

In the class of 40 students, 22 are girls and 18 are boys. Thus, the ratio of girls to boys becomes:

The above fraction can be reduced further since 2 is a common factor in both 22 and 18. Thus

In ratio form, girls: boys=11:9

Thus, the ratio of girls to boys in a class of 40 students is 11 to 9.