1.
0.45÷5=
Correct Answer
D. 0.09
Explanation
When dividing 0.45 by 5, we can think of it as finding how many times 5 fits into 0.45. Since 5 does not fit evenly into 0.45, we need to use decimals. We start by placing a decimal point in the quotient. Then, we divide 5 into 45, which gives us 9. Finally, we place the decimal point in the quotient to get 0.09. Therefore, the correct answer is 0.09.
2.
The equivalent rational number of -3/5.
Correct Answer
D. -9/15
Explanation
The equivalent rational number of -3/5 is -9/15 because when we multiply the numerator and denominator of -3/5 by the same number (in this case, 3), we get -9/15. This is because multiplying both the numerator and denominator by the same number does not change the value of the fraction. Therefore, -9/15 is the equivalent rational number of -3/5.
3.
The equivalent rational number for
-12/30 with denominator 5.
Correct Answer
B. -2/5
Explanation
The given rational number is -12/30. To find the equivalent rational number with denominator 5, we need to simplify the fraction. By dividing both the numerator and denominator by their greatest common divisor (which is 6), we get -2/5. Therefore, the correct answer is -2/5.
4.
The increasing order of -3,-2,-5,0.
Correct Answer
A. -5,-3,-2,0
Explanation
The correct answer is -5,-3,-2,0. This is the increasing order of the given numbers. Starting from the smallest number, which is -5, the numbers are arranged in ascending order, with each subsequent number being greater than the previous one. The final number in the sequence is 0, which is the largest number among the given numbers.
5.
The average of 4.5,2.7,3.3.
Correct Answer
B. 3.5
Explanation
The correct answer is 3.5 because to find the average, you need to add up all the numbers and then divide by the total number of values. In this case, the sum of 4.5, 2.7, and 3.3 is 10.5. Dividing 10.5 by 3 (the total number of values) gives us an average of 3.5.
6.
Rational numbers are denoted by "R".
Correct Answer
B. False
Explanation
The statement "Rational numbers are denoted by 'R'" is false. Rational numbers are actually denoted by the letter "Q". The letter "R" is used to represent the set of real numbers, which includes both rational and irrational numbers.
7.
Integers are denoted by "Z"
Correct Answer
A. True
Explanation
The given correct answer is true because integers are indeed denoted by the symbol "Z". In mathematics, "Z" represents the set of all integers, which includes positive numbers, negative numbers, and zero. This notation helps to distinguish integers from other types of numbers, such as rational numbers (denoted by "Q") or real numbers (denoted by "R"). Therefore, the statement is accurate.
8.
5/6,1/6,7/6 are equivalent rational numbers.
Correct Answer
B. False
Explanation
The given statement is false. 5/6, 1/6, and 7/6 are not equivalent rational numbers. Equivalent rational numbers have the same value or can be simplified to the same fraction. In this case, 5/6 and 1/6 have different values and cannot be simplified to the same fraction. Additionally, 7/6 is an improper fraction and cannot be equivalent to either 5/6 or 1/6. Therefore, the correct answer is false.
9.
Every Integer is a Rational number.
Correct Answer
A. True
Explanation
Every integer is a rational number because a rational number can be expressed as the ratio of two integers. Since every integer can be written as the ratio of itself and 1, it is considered a rational number.