Answer:
can u please add the statements.
Step-by-step explanation:
5400 is ur answer .
ans: 5400 is the surface area
First term, a
1
=4
Second term, a
2
=8
Common difference, d=a
2
=a
1
d=8−4=4
∴ The common difference is 4
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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(D) hope this helps kxjdndldjdkwpwnx