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

a. 3/4 ÷ 1/8 = 6

step-by-step explanation:

in the question, the number line represents 3/4 divided into 6 equal units. each arrow represents a unit and there are a total of six arrows.

the size of each unit is 1/8 as shown.

showing that 1/8 divides 3/4 into 6 divisions:

3/4 ÷ 1/8

= 3/4 x 8/1

= 3/1 x 8/4

= 3 x 2

= 6

hence, the number line represents six divisions given by 3/4 ÷ 1/8.

x + y = 90 5x – 10y = 90 90 – 10y = 5x 90 + 10y = 5x

step-by-step explanation:

last month maria hiked the 5-mile mountain trail a number of times and she hiked the 10-mile canal trail several times. let x represent the number of times she hiked the 5-mile trail, and let y represent the number of times she hiked the 10-mile trail. if she hiked a total of 90 miles, which equation can be used to find the number of times maria hiked each trail? x + y = 90 5x – 10y = 90 90 – 10y = 5x 90 + 10y = 5x