Twelve less than thrice a number Which of the following translates the phrase above into a mathematical expression?
A. 3x - 12
B. 12 - 3x
C. 12x - 2
D. 3x + 12
We need to form a mathematical expression from the given word problem.
Let the unknown number be x.
Thrice a number is three times = 3x
Twelve less than thrice a number = 3x-12
Thus, the mathematical expression from the word problem is 3x-12
Therefore, the Correct Answer is A.
More Questions on TEAS 7 Math
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Q #1: A sweater that normally sells for $95 is marked 30% off. Which of the following estimates the sale price of the sweater?
A. $67
B. $30
C. $22
D. $63
Answer Explanation
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.
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Q #2: When the marks of a science test are graphed, the distribution of markss is symmetric with the majority of weights centered around a single peak. Which of the following describes the shape of this distribution?
A. Uniform
B. Skewed right
C. Bell-shaped
D. Bimodal
Answer Explanation
In a bell-shaped curve, the data distribution is symmetric around a single peak. The centering of data around a single peak means the mean, mode and median of the test are all equal to each other.
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Q #3: As a person climbing a mountain increases walking speed, the rate of calories burned, height traveled, and energy expended also increase. Which of the following is the independent variable?
A. Walking speed
B. Energy
C. Calories
D. Height
Answer Explanation
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.
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Q #4: A couple dining at a restaurant receives a bill for $58.60. They wish to leave a 16% gratuity. Which of the following is the estimated gratuity?
A. $8.48
B. $6.40
C. $9.38
D. $7.00
Answer Explanation
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.
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Q #5: An athlete runs 7 miles in 45 minutes and then changes their pace to run the next 3 miles in 15 minutes. Overall, what is the average time in minutes it takes the athlete to run 1 mile?
A. 9.5 minutes
B. 9 minutes
C. 6 minutes
D. 10minutes
Answer Explanation
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.
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Q #6: How many yards are in 27 feet?
A. 3 yards
B. 18 yards
C. 6 yards
D. 9 yards
Answer Explanation
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.
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Q #7: One gallon of cleaning solution requires 10 oz of ammonia. If the maintenance department needs 51 gallons of solution to clean all of the floors, how much ammonia is needed?
A. 510 gallons
B. 51 gallons
C. 510 oz
D. 51 oz
Answer Explanation
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 10 oz 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.
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Q #8: 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?
A. $16.20
B. $84.20
C. $43.20
D. $27.00
Answer Explanation
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
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Q #9: The scatter plot below shows the relationship between the number of hours a student plays golf and the student’s class attendance. Which of the following types of correlation is shown on the scatter plot?
A. Positive
B. Positive and negative
C. No correlation
D. Negative
Answer Explanation
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
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Q #10: Which of the following statements is true about the following graph?
A. The Chargers points per game decreased between seasons five times between 1996 and 2015
B. The Chargers scored their lowest number of points per game in 1999-2000 season
C. The Chargers scored their greatest number of points per game in the 2002-03 season
D. None of the above
Answer Explanation
We analyze the given statement with the graph given as follows:
For option a: the points per game decreased five times between 1996 and 2015. So, the statement is true.
For option b: the lowest points scored per game was in 1998-99 season. So, the statement is false.
For option c: 2008-09 was the season the chargers scored the greatest number of points per game and not 2002-03 as claimed in the statement. So, this statement is not true.
