The circumference of a DVD disc is 28.26 cm
This number is natural, whole, integer, and rational.
Whole numbers are numbers such as 0, 1, 2, ... This is a whole number.
Natural numbers can also be counting numbers. They are the whole numbers, but starting at 1, not 0. This is a natural number.
Integers are whole numbers with negatives. This is an integer.
Rational numbers are any numbers that can be written as a fraction. We can write this as 4563/1, so it is rational.
The average score of all the students in both classes is 84.
<h3>How to calculate the average?</h3>
The class with 30 students had an average score of 80 on a test. The total score will be:
= 30 × 80
= 2400
A class with 20 students had an average score of 90 on the same test. The total score will be:
= 20 × 90
= 1800
Total scores = 2400 + 1800 = 4200
Number of students = 20 + 30 = 50
The average score will be:
= Total score / Total students
= 4200 / 50
= 84
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Answer:
you domb if you dont know the answer B
Step-by-step explanation:
