The grades of a statistics midterm are normally distributed with a mean of 70 and a standard deviation of 2. Without using a calculator, what is the probability that a student will receive a grade between 74 and 76? 4.30% 2.15% 34.12% 13.6%

.13.5%

Step-by-step explanation:

The probability that a student will receive a grade between 74 and 76 is calculated as follows:

µ+2σ=70+2(2)=70+4=74

µ+3σ=70+3(2)=70+6=76

From the above empirical rule it can be observed that 13.5% of observations fall in between 1 and 2 standard deviations above the mean.

Therefore, the probability that a student will receive a grade between 74 and 76 is 13.5%.

Thus, the correct options is A.13.5%.

a.   since the profit made in 2012 is equal to the profit made in 2014, the profit is symmetric about the line y = 120,000.

step-by-step explanation:

answer: solve 5\cdot 2^x=2405⋅2  

x

=2405, dot, 2, start superscript, x, end superscript, equals, 240.

solution

to solve for xxx, we must first isolate the exponential part. to do this, divide both sides by 555 as shown below. we do not multiply the 555 and the 222 as this goes against the order of operations!

\begin{aligned} 5\cdot 2^x& =240 2^x& =48 \\ \end{aligned}  

5⋅2  

x

2  

x

​    

=240

=48

​

step-by-step explanation: