Formulas

Question 1

Formula for 95% confidence interval

Answer 1

Mean +/- 1.96 * SD / square root of n (sample size)

Question 2

Formula for 99% CI

Answer 2

Mean +/- 2.58* SD / square root of n

2.58 is the z score for a 99% CI

Question 3

Cardiac Output

Answer 3

CO = SV x HR

Question 4

Law of conservation of mass (flow in must = flow out)

Answer 4

A1 x V1 = A2 x V2 (area and velocity of a tube)

Question 5

Ejection Fraction

Answer 5

EF = SV / EDV (normal should be > 55%)

Question 6

Resistance to flow

Answer 6

resistance is inversely proportional to the radius to the 4th power