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 class of 40 students has 18 boys and 22 girls. What is ratio of girls to boys in the class?
A. 11:9
B. 20:9
C. 9:11
D. 20:11
Answer Explanation
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.
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Q #2: 3(3x+3)=8x+5 Solve the equation above for x. Which of the following is correct?
A. 1
B. 4
C. -1
D. -4
Answer Explanation
We use the order of operation to solve for the unknown value of x.
3(3x+3)=8x+5
Multiply 3 with each number in the brackets
(3*3x)+(3*3)=8x+5
9x+9=8x+5
Subtract 9 from both sides
9x+9-9=8x+5-9
9x=8x-4
Subtract 8x on both sides
9x-8x=8x-8x-4
x=-4
Thus, the unknown value of x is -4.
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Q #3: 3.60*0.75 Simplify the expression above. Which of the following is correct?
A. 0.027
B. 27
C. 0.27
D. 2.7
Answer Explanation
To solve the equation this equation, we compute the multiplication of the two numbers using the calculator
3.60 * 0.75 = 2.7
