twelve less than thrice a number which of the following translates the phrase above into a mathematical expression

ATI TEAS 7

Practice Math TEAS TEST

1. What is the mathematical expression for 'Twelve less than thrice a number'?

A. 3x-12
B. 12-3x
C. 3-12x
D. 12x-3

Correct answer: A

Rationale: The phrase 'thrice a number' translates to 3x, and 'twelve less than' means subtracting 12 from it. Therefore, the correct expression is 3x-12. Choice B, '12-3x', represents '12 less than a number thrice,' which is the opposite of the given phrase. Choice C, '3-12x', does not correctly interpret the phrase provided. Choice D, '12x-3', represents 'a number thrice less than twelve,' which is not the same as the original phrase.

2. Simplify the following expression: 5/9 × 15/36

A. 5/36
B. 8/27
C. 10/17
D. 15/27

Correct answer: A

Rationale: To simplify the given expression, multiply the numerators together and the denominators together. 5/9 × 15/36 = (5 × 15) / (9 × 36) = 75 / 324. Now, simplify the resulting fraction by finding the greatest common divisor (GCD) of 75 and 324, which is 3. Divide both the numerator and denominator by 3 to get the simplified fraction: 75 ÷ 3 / 324 ÷ 3 = 25 / 108. Therefore, the simplified form of 5/9 × 15/36 is 25/108, which is equivalent to 5/36. Choice A, 5/36, is the correct answer. Choice B, 8/27, is incorrect as it does not match the simplified form of the expression. Choice C, 10/17, is unrelated and does not result from the given multiplication. Choice D, 15/27, does not correspond to the simplification of the given expression.

3. How do you convert Fahrenheit to Celsius and Celsius to Fahrenheit?

A. Fahrenheit to Celsius: Subtract 32, then divide by 1.8; Celsius to Fahrenheit: Multiply by 1.8, then add 32
B. Fahrenheit to Celsius: Subtract 32, then divide by 2; Celsius to Fahrenheit: Multiply by 1.8, then add 20
C. Fahrenheit to Celsius: Multiply by 2, then add 32; Celsius to Fahrenheit: Subtract 32, then divide by 1.8
D. Fahrenheit to Celsius: Subtract 30, then divide by 1.8; Celsius to Fahrenheit: Multiply by 2, then add 32

Correct answer: A

Rationale: To convert Fahrenheit to Celsius, you start by subtracting 32 from the Fahrenheit temperature and then divide the result by 1.8. This formula accounts for the freezing point of water at 32°F and the conversion factor to Celsius. To convert Celsius to Fahrenheit, you multiply the Celsius temperature by 1.8 and then add 32. This process takes into consideration the conversion factor from Celsius to Fahrenheit and the freezing point of water. Choice B is incorrect as dividing by 2 instead of 1.8 would yield an inaccurate conversion. Choice C is incorrect as it involves incorrect operations for both conversions. Choice D is incorrect as subtracting 30 instead of 32 for Fahrenheit to Celsius and multiplying by 2 instead of 1.8 for Celsius to Fahrenheit would provide incorrect results.

4. If you pull an orange block from a bag of 3 orange, 5 green, and 4 purple blocks, what is the probability of consecutively pulling two more orange blocks without replacement?

A. 1/12
B. 3/55
C. 1/55
D. 2/33

Correct answer: B

Rationale: To calculate the probability of pulling two more orange blocks consecutively without replacement after the initial orange block is pulled, we need to multiply the probabilities. After the first orange block is pulled, there are 2 orange blocks left out of a total of 11 blocks remaining. So, the probability of pulling a second orange block is 2/11. Therefore, the overall probability is (3/12) * (2/11) = 3/55. Choice A (1/12) is incorrect because it only considers the probability of the first orange block being pulled. Choice C (1/55) is incorrect as it represents the probability of pulling two orange blocks in a row, not the consecutive pulls after the initial pull. Choice D (2/33) is incorrect as it does not reflect the correct calculation for the consecutive pulls of orange blocks.

5. What is the median of the data set below: 5, -3, 10, -2, 0?

A. 10
B. 0
C. 5
D. 2

Correct answer: B

Rationale: To find the median, we first need to arrange the data set in ascending order: -3, -2, 0, 5, 10. The median is the middle value in the ordered set. As there are 5 numbers, the middle value is the third number, which is 0. Therefore, the correct answer is 0. Choice A (10) and Choice D (2) are not correct because they are not the middle values once the data set is ordered. Choice C (5) is also incorrect as it is not the middle value in the ordered data set.