Question

What was Helen's nine week grade in marine biology round to 2 decimal places

Answer 1

From the question, the test scores were 85, 57 and 82,

To find the 55% average test score below,

$\begin{gathered} Av\text{ test score=}\frac{85+57+82}{3}=\frac{224}{3} \\ 55\text{\% of }\frac{224}{3}=\frac{55}{100}\times\frac{224}{3}=\frac{616}{15}=41.067 \end{gathered}$

The daily scores were 75, 86, 98, 97, 65, 79 and 85,

To find the 20% average daily score,

$\begin{gathered} Av\text{ daily score=}\frac{75+86+98+97+65+79+85_{}}{7}=\frac{585}{7} \\ 20\text{\% of }\frac{585}{7}=\frac{20}{100}\times\frac{585}{7}=16.714 \end{gathered}$

The group presentation scores were 86, 87, 65 and 91

To find the 25% average group presentation score,

$\begin{gathered} Av\text{ group presentation=}\frac{86+87+65+91}{4}=\frac{329}{4} \\ 25\text{\% of }\frac{329}{4}=\frac{25}{100}\times\frac{329}{4}=20.563 \end{gathered}$

Helen's nine weeks score/grade will be,

$=41.067+16.714+20.563=78.344=78.34\text{ (2 d.p)}$

Answer is 78.34 (2 decimal places)