Answer:
The value of the determinant is 0.
Step-by-step explanation:
Since it is a 3 x 3 determinant, we can calculate its value by the Law of Sarrus:



The value of the determinant is 0.
<u><em>Explanation</em></u>
5 students got 6 mark each, 4 students got 7 marks each, 7 students got 8 marks each, 10 students got 9 marks each and 4 students got 10 marks each.
(a) <u>Range is the difference of highest mark and lowest mark.</u> Here, the highest mark is 10 and lowest mark is 6.
So, the range of mark 
(b) Total number of students in the group 
(c) Mean is the <u>simple average.</u> So, for finding the Mean, we will divide the total marks obtained by all students by the total number of students.
Total marks obtained by all students

So, the Mean mark of the group 
Answer:
B
Step-by-step explanation:
Answer:
Equation: 3x + 7 = 16
Unknown Number: 3
Step-by-step explanation:
You must first develop an equation representing this problem:
3x + 7 = 16
Then, you can solve for the unknown number.
3x + 7 = 16
3x = 9
x = 3