Dr. Denscombe randomly assigned 10 participants to drink a caffeinated beverage and another 10 participants to drink a noncaffeinated beverage. He then recorded their average driving speed over a 10-minute period. Caffeinated drivers averaged 50 mph with a variance of 20 and noncaffeinated drivers averaged 30 mph with a variance of 20. What is t

t = 10

Step-by-step explanation:m

 Given that; n₁ = 10, n₂ = 10

ж₁ = 50, ж₂ = 30

Sˣ₁ = 20, Sˣ₂ = 20

Now using TEST STATISTICS

t = (ж₁ - ж₂) / √ ( Sˣ₁/n₁ + Sˣ₂/n₂ )

so we substitute our figures

t = ( 50 - 30 ) / √ ( 20/10 + 20/10 )

t = 20 / √4

t = 10

341

step-by-step explanation:

all you have to do is 9x31 (which equals 279) and then 20x31 (which equals 620). then you have to subtract. 620-279=341.