SOLUTION: In a text if a student have scored 80 marks in one of the subjects. His average mark in eight subjects would be 62. If he had scored 64 marks in that same subject with the scores i

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Question 1092929: In a text if a student have scored 80 marks in one of the subjects. His average mark in eight subjects would be 62. If he had scored 64 marks in that same subject with the scores in the remaining seven subjects on changed. The average mark would be m. Find the value of m.
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
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In a test if a student have scored 80 marks in one of the subjects.
His average mark in eight subjects would be 62.
If he had scored 64 marks in that same subject with the scores in the remaining seven subjects unchanged, the average mark would be m.
Find the value of m.
:
let a = the average score in the 7 subjects
" if a student have scored 80 marks in one of the subjects, his average mark in eight subjects would be 62."
%28%287a%2B80%29%29%2F8 = 62
multiply both sides by 8
7a + 80 = 496
7a = 496 - 80
a = 416/7
a = 59.43
" If he had scored 64 marks in that same subject with the scores in the remaining seven subjects unchanged, the average mark would be m.
Find the value of m."
m = %28%287%2859.43%29%2B64%29%29%2F8
m = %28%28416%2B64%29%29%2F8
m = 480%2F8
m = 60 is the average mark if he scores 64 in the 8th test