Answer:
The median and mode of the students grade is 70.
Most of the students scored between 40 and 100.
Step-by-step explanation:
From the provided information it can be seen that the mean of the distribution is, <em>μ</em> = 70 and the standard deviation is, <em>σ</em> = 15.
For a Normal distributed data the mean, median and mode are the same.
So, the median and mode of the students grade is 70.
The standard deviation of the data represents the spread of the observation, i.e. how dispersed the values are along the curve.
In statistics, the 68–95–99.7 rule, also recognized as the empirical rule, is a shortcut used to recall that 68.27%, 95.45% and 99.73% of the values of a Normally distributed data lie within one, two and three standard deviations of the mean, respectively.
Assuming that maximum marks of the exam is 100, it can be said that most of the students scored between 40 and 100.
Constraint 1:
Let the total number of running shoes be = R
Let the total number of leather boots be = L
As the given number of total shoes are 48,
The equations becomes,
R + L = 48............(1)
Constraint 2:
As running shoes are twice the leather boots, equation becomes,
R = 2L..............(2)
Putting the value of R from equation(2) in equation (1)
Now putting the value of L in equation(2)
R= 2L
R =
R=32
Hence, Amanda needs 16 pairs of leather boots and 32 pairs of running shoes.