what kind of number system is commonly used in the united states

HESI A2

Math HESI A2 Practice Test

1. Which number system is commonly used in the United States?

A. Tertiary
B. Decimal
C. Napoleonic
D. Binary

Correct answer: B

Rationale: The correct answer is B: Decimal. The decimal system, also known as the base-10 system, is the standard system for denoting integer and non-integer numbers in the United States and many other countries. In the decimal system, numbers are represented using 10 digits (0-9). Choices A, C, and D are incorrect. Tertiary, Napoleonic, and Binary number systems are not commonly used for general number representation in the United States.

2. What is the result of the expression 4/5 + 6/7?

A. 1 23/35
B. 2 5/7
C. 1 1/7
D. 1 3/4

Correct answer: A

Rationale: To add fractions with different denominators, you first need to find a common denominator. In this case, the common denominator for 5 and 7 is 35. Then, convert each fraction to have a denominator of 35. 4/5 becomes 28/35, and 6/7 becomes 30/35. Adding these fractions together gives 58/35, which simplifies to 1 23/35. Therefore, the correct answer is A, 1 23/35. Choice B, 2 5/7, is incorrect because it does not match the correct result. Choice C, 1 1/7, is incorrect as it is not the simplified form of the sum of the fractions. Choice D, 1 3/4, is incorrect as it is a different result and not the sum of 4/5 and 6/7.

3. Subtract 15 3/4 - 8 2/5.

A. 7 7/20
B. 6 7/20
C. 9 1/5
D. 8 2/5

Correct answer: A

Rationale: To subtract mixed numbers, find a common denominator. In this case, the common denominator is 20. Convert 15 3/4 to 15 15/20. Then, subtract 15 15/20 - 8 8/20 = 7 7/20. Therefore, the correct answer is A. Choice B is incorrect as it does not match the result of the subtraction. Choice C is incorrect as it is not the result of the subtraction. Choice D is incorrect as it represents the second number being subtracted, not the result of the subtraction.

4. In a local baseball team, 4 players, which represent 5% of the team, have long hair, and the rest have short hair. How many short-haired players are there on the team?

A. 72
B. 74
C. 76
D. 78

Correct answer: C

Rationale: Given that 4 players represent 5% of the team, let's denote the total number of players as x. The equation to represent this situation is 0.05x = 4. Solving for x, we get x = 80, which is the total number of players on the team. Since 4 players have long hair, the remaining players have short hair, which is 80 - 4 = 76. Therefore, there are 76 short-haired players on the team. Choices A, B, and D are incorrect as they do not consider the total number of players correctly, leading to inaccurate calculations.

5. The least common multiple (LCM) of two numbers is the smallest number that is a multiple of both. Which of the following represents the LCM of 14 and 21?

A. 42
B. 63
C. 84
D. 168

Correct answer: C

Rationale: Rationale: To find the least common multiple (LCM) of 14 and 21, we need to determine the smallest number that is a multiple of both 14 and 21. First, list the multiples of 14: 14, 28, 42, 56, 70, 84, ... Next, list the multiples of 21: 21, 42, 63, 84, ... The smallest number that appears in both lists is 42. Therefore, the LCM of 14 and 21 is 42.