Stats and Mechanics Exam

Question 1

If data is coded using y=(x+a)/b, what is the mean and s.d. of coded data

Answer 1

mean of new data = (x+a)/b

s.d. of new data = x/b

Question 2

What equation is used to find outliers?

Answer 2

Outliers = UQ +/- k(UP-LQ)

Question 3

How to draw a cumulative frequency diagram

Answer 3

Plot each point using the upper class boundary for x and cumulative frequency for y. Join points with a curve

Question 4

How to calculate the frequency density for a histogram

Answer 4

Frequency density = frequency/class width

Question 5

When can a binomial distribution be used to model X

Answer 5

• fixed number of trials
• two possible outcomes (success and failure)
• there is a fixed probability of success, p
• the trials are independent of each other

Question 6

What is the null hypothesis and the alternative hypothesis

Answer 6

H0, null hypothesis is the hypothesis that you assume to be true
H1, alternative hypothesis tells you about the parameter if your assumption is shown to be wrong

Question 7

SUVAT using S, U, V and T

Answer 7

s = ((u+v)/2)t

Question 8

SUVAT using V, U, A and T

Answer 8

v = u + at

Question 9

SUVAT using V, U, A and S

Answer 9

v^2 = u^2 + 2as

Question 10

SUVAT using S, U, A and T

Answer 10

s = ut + 1/2(at^2)

Question 11

SUVAT using S, A, V and T

Answer 11

s = vt + 1/2(at^2)

Question 12

How to work out velocity from displacement

Answer 12

Velocity = ds/dt

Question 13

How to work out acceleration from velocity or displacement

Answer 13

a = dv/dt
or
a = d^2s/dt^2