what is a common denominator

ATI TEAS 7

Practice Math TEAS TEST

1. What is a common denominator?

A. A shared multiple of two denominators
B. A shared factor of two numerators
C. A number that is the same in all fractions
D. A number that divides evenly into both fractions

Correct answer: A

Rationale: A common denominator is a shared multiple of the denominators in a set of fractions. It is necessary when adding or subtracting fractions to have a common denominator to ensure that the fractions can be combined accurately. Choice B is incorrect because the common denominator is related to the denominators, not the numerators. Choice C is incorrect because while the common denominator is the same in all fractions being added or subtracted, it is not necessarily a number that is the same in all fractions. Choice D is incorrect because a common denominator is a multiple of the denominators, not a number that divides evenly into both fractions.

2. In a fraction, which number is the numerator and which is the denominator?

A. Numerator: top, Denominator: bottom
B. Numerator: bottom, Denominator: top
C. Numerator: left, Denominator: right
D. Numerator: right, Denominator: left

Correct answer: A

Rationale: The correct answer is A: 'Numerator: top, Denominator: bottom.' In a fraction, the numerator is the top number, representing the part of the whole being considered, while the denominator is the bottom number, indicating the total number of equal parts into which the whole is divided. Choices B, C, and D are incorrect because they provide inaccurate descriptions of the numerator and denominator positions in a fraction.

3. At the beginning of the day, Xavier has 20 apples. At lunch, he meets his sister Emma and gives her half of his apples. After lunch, he stops by his neighbor Jim's house and gives him 6 of his apples. He then uses 3/4 of his remaining apples to make an apple pie for dessert at dinner. At the end of the day, how many apples does Xavier have left?

A. 4
B. 6
C. 2
D. 1

Correct answer: D

Rationale: Xavier gives away half of his 20 apples (10), then gives 6 more apples, leaving him with 4 apples. He uses 3/4 of the remaining 4 apples (3) for the pie, leaving him with 1 apple at the end of the day. Therefore, the correct answer is 1. Choices A, B, and C are incorrect because they do not accurately reflect the calculations of apples given away and used for the pie, resulting in the remaining amount of 1 apple.

4. In a city with a population of 51,623, 9.5% of the population voted for a new proposition. How many people approximately voted?

A. 3,000 people
B. 5,000 people
C. 7,000 people
D. 10,000 people

Correct answer: B

Rationale: To find the number of people who voted, you need to calculate 9.5% of the total population of 51,623. 9.5% of 51,623 is approximately 0.095 x 51,623 = 4,999.85, which is rounded to approximately 5,000 people. Therefore, the correct answer is 5,000 people. Choice A, 3,000 people, is incorrect as it is lower than the calculated value. Choice C, 7,000 people, is incorrect as it is higher than the calculated value. Choice D, 10,000 people, is incorrect as it is much higher than the calculated value.

5. What defines an integer?

A. A whole number (not a fraction or decimal!) that can be positive, negative, or zero
B. A number with a decimal point
C. A fraction
D. A percentage

Correct answer: A

Rationale: An integer is a whole number that can be positive, negative, or zero. It does not include fractions or decimals. Choice B, 'A number with a decimal point,' is incorrect because integers do not have decimal points. Choice C, 'A fraction,' is incorrect because integers are not expressed as ratios of two integers. Choice D, 'A percentage,' is incorrect because integers are not necessarily related to proportions out of 100.