Question

Alex wants to calculate his term mark in mathematics. It is to be based on 6 assignments, all equally weighted. He scored 82%,74%,66%, 83%, and 75% on his first five assignments. What mark will Alex need on his sixth assignments in order to achieve a term mark of 80%?

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asked 2021-03-02
Alex wants to calculate his term mark in mathematics. It is to be based on 6 assignments, all equally weighted. He scored 82%,74%,66%, 83%, and 75% on his first five assignments. What mark will Alex need on his sixth assignments in order to achieve a term mark of 80%?

Answers (1)

2021-03-03
Let x be the score he needs to receive on the sixth assignment. If the needs a mean score of 80%, then:
mean score=sun of his scores/number of scores/number
\(\displaystyle{80}\%=\frac{{{82}\%+{74}\%+{66}\%+{83}\%+{75}\%+{x}}}{{6}}\)
\(\displaystyle{80}\%=\frac{{{380}\%+{x}}}{{6}}\)
480%=380%+x
100%=x
He must then score 100% on his sixth assignment to achieve an 80% for the the term.
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