91影视

The gypsy moth is a serious threat to oak and aspen trees. A state agriculture department places traps throughout the state to detect the moths. When traps are checked periodically, the mean number of moths trapped is only $0.5$, but some traps have several moths. The distribution of moth counts is discrete and strongly skewed, with standard deviation $0.7$.

Population mean$\left(渭\right)=0.50$

Population standard deviation$\left(蟽\right)=0.7$

Sample size $\left(n\right)=50$

The mean and standard deviation can be calculated as:

${渭}_{\stackrel{炉}{x}}=渭=0.5$

$$\begin{gathered} {蟽}_{\stackrel{炉}{x}}=\frac{蟽}{\sqrt{n}} \\ =\frac{0.7}{\sqrt{50}} \\ =0.0990 \end{gathered}$$

The required mean and standard deviation are $0.5$and $0.0990$respectively

The gypsy moth is a serious threat to oak and aspen trees. A state agriculture department places traps throughout the state to detect the moths. When traps are checked periodically, the mean number of moths trapped is only $0.5$, but some traps have several moths. The distribution of moth counts is discrete and strongly skewed, with standard deviation$0.7.$

The probability that average number of months is greater than $0.6$can be calculated as:

$$\begin{gathered} P(\stackrel{炉}{x}鈮�0.6)=P\left(Z鈮�\frac{0.6-0.5}{\frac{0.7}{\sqrt{30}}}\right) \\ =P(Z鈮�1.01) \\ =0.1562 \end{gathered}$$

Thus, the probability is $0.1562$.