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: A baker is using a cookie recipe that call for 2 ¼ cups of flour to yield 36 cookies. How much flour will the baker need to make 90 cookies using the same recipe?
A. 6 ¾ cups
B. 5 5/8 cups
C. 10 1/8 cups
D. 4 ¾ cups
Answer Explanation
We are asked to find the number of cups of flour that will be used to make 90 cookies.
Letting x be the number of cups of flour and setting the proportion equation with number of cookies on numerator and number of cups of flour on the denominator. We have
Solve the value of x by cross-multiplying
We convert the mixed fraction into improper fraction in order to carry out multiplication
\(x =\ \frac{9}{4}\ cups\ *\ 90\ cookies\ *\ \frac{1}{36}\ cookies\)
The number of cups of flour needed to make 90 cookies is 5.625 cups, which is equal to 5 5/8 cups(Choice B).
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Q #2: To determine the cost of a pizza, the pizza parlor considers the diameter of the pizza, the number of toppings, and the amount of cheese. Which of the following is the dependent variable?
A. Amount of pizza
B. Dimeter of the pizza
C. Cost of the pizza
D. Number of toppings
Answer Explanation
We are asked to find the dependent variable from the given scenario. A dependent variable is one which varies with another variable. In this case, the cost of the pizza will change with the change in diameter of the pizza, number of toppings, and amount of cheese. In other words, the cost of the pizza depends on the three variables.
Therefore, cost is the dependent variable while the diameter of the pizza, number of toppings and amount of cheese are independent variables.
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Q #3: A circle has an area of 49 in2. Which of the following is the circumference of the circle in terms of pi ( )?
A. 7 π in
B. 14 π in
C. 28 π in
D. 3.5 π in
Answer Explanation
We need to find the circumference of the circle from the given area.
To find the circumference, we need to find the radius of the circle from the given area.
Let r be the radius of the circle, and the area of the circle is given by
Substituting the value of area in the above equation becomes
Dividing both sides by pi and taking square root on both sides yields
The radius of the circle is 7 in. and the circumference of the circle is given by the relation:
