Which of the following is the best approximation of 10 times the positive square root of 20?
A. 100.0
B. 44.7
C. 200.0
D. 89.4
We use the calculator to determine the positive square root of 20, which is then multiplied by 20.
Using the calculator, 
Multiplying the square root above with 10 becomes
The approximate value is 44.7.
Therefore, the Correct Answer is B.
More Questions on TEAS 7 Math
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Q #1: Which of the following is the best approximation of 10 times the positive square root of 20?
A. 100.0
B. 44.7
C. 200.0
D. 89.4
Answer Explanation
We use the calculator to determine the positive square root of 20, which is then multiplied by 20.
Using the calculator,
Multiplying the square root above with 10 becomes
The approximate value is 44.7.
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Q #2: Which of the following is the length of the unknown leg of a right triangle that has one leg length of 8 feet and a hypotenuse of 12 feet? (Round to the nearest tenth.)
A. 4 feet
B. 14.4 feet
C. 8.9 feet
D. 40 feet
Answer Explanation
We are asked to find the one of the lengths of a right-angled triangle, we use the Pythagoras theorem to find the unknown length.
First, we label the triangle as below and let the unknown length be x.
Then, we apply the Pythagoras theorem to find the value of x as:
The value of the unknown length is approximately 8.9 feet.
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Q #3: A bucket containing 2 4/5 gallons of water is 1/3 full. How many gallons of water is in one fully filled bucket?
A. 14/15
B. 2 7/15
C. 8 2/5
D. 6 4/5
Answer Explanation
We are asked to find the number of gallons full tank can hold. The fraction of full tank is 1.
First, we let x be the number of gallons in full tank. Then, set the proportion equation by setting the number of gallons on the numerator and fraction of tank on denominator as follows.
Convert the mixed fraction into proper fraction and cross-multiply to find the value of x.
Converting 42/5 to a mixed fraction is 8 2/5. Thus, when the tank is full, it holds 8 2/5 gallons of water.
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Q #4: A macaroni and cheese recipe calls for 1/3 cup of flour for every 1 1/5 cup of milk. To make a bigger batch, the chef uses 2 cups of flour. Which of the following would be the amount of milk needed for the bigger batch?
A. 7 1/5 cups
B. 2 2/5 cups
C. 3 8/15 cups
D. 6 cups
Answer Explanation
We are being asked to find the amount of milk needed. This is a proportion problem, which compares the amount of flour to that of milk. Letting x represent the amount of milk required, we set up the proportion with flour on the numerator and amount of milk in denominator as follows:
Change the mixed fraction of 1 1/5 into improper fraction as follows
The proportion equation becomes
Cross-multiply to solve for x
As an mixed fraction, 36/5 becomes 7 1/5. Therefore, 7 1/5 cups of milk are needed to make a big batch of 2 cups.
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Q #5: Which of the following is an appropriate unit of measure to express the length of a dollar bill?
A. Decameters
B. Kilometers
C. Centimeter
D. Meters
Answer Explanation
Centimeter is the appropriate unit to measure the length of a dollar bill.
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Q #6: Which of the following is the equivalence in pounds for 50 kg? (2.2 lb=1 kg)
A. 52.2 lb
B. 22.7 lb
C. 110 lb
D. 220 lb
Answer Explanation
We are asked to convert kg to pounds using the given relation. Letting x to represent the lb we are looking for.
Nest, we set the proportion with kg in the numerator and lb on the denominator as follows.
We find the value of x by cross-multiplication
The value of x is 110 lb.
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Q #7: Four friends are sharing a pizza. One friend eats half of the pizza. The other three friends equally divide the rest among themselves. What portion of the pizza did each of the other three friends receive?
A. 1/6
B. 1/3
C. ¼
D. 1/5
Answer Explanation
What fraction of the pizza the other three friends get is what is asked to find.
First, the pizza is whole, representing a value of 1. Then, one friend ate half of the pizza. Thun, the fraction of the pizza the friend gets is:
First friend eats =1/2 of 1=1/2
Remaining fraction of the pizza=1-1/2=1/2
Now, the three friends share ½ amongst themselves equally. Then, each friend gets
The three friends each gets 1/6 of the pizza.
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Q #8: A child has collected 50 pennies, 40 nickels, 25 dimes, and 5 quarters. Which of the following charts accurately organizes the number of coins? Chart 1 Chart 2 Chart 3 Chart 4
A. Chart 1
B. Chart 2
C. Chart 3
D. Chart 4
Answer Explanation
By inspection, we find the corresponding values of the given denominations in the following manner.
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Q #9: Solve for x in the equation above.
A. x=rwy+z
B. x=rw(y-z)
C. x=y(z+rw)
D. x=rwy+z
Answer Explanation
We are asked to make x the subject of the formula.
First, we add z to both sides of the equation
Multiply both sides by y
The above equation can be rearranged into
Thus, the formula for finding the value of x is y(z+rw).
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Q #10: Which of the following is the mean of the test scores listed below? 100, 78, 47, 84, 93, 78
A. 80
B. 78
C. 96
D. 87
Answer Explanation
The mean of a data set is the total scores divided by the number of tests.
Total test scores =100+78+47+84+93+78=480
Number of tests =6
Mean test score =480/6=80
The mean test score is 80.
