Mr. Schwartz builds toy cars. He begins the week with a supply of 85 wheels, and uses 4 wheels for each car he builds. Mr. Schwa

Response:

(a) 3, 5, and 6

Detailed explanation:

In this study, 43 participants will be treated with a gel containing tooth-whitening agents, while the remaining 42 will receive a placebo. Consequently, a placebo is in use.

The selection process for the 43 individuals receiving the gel will be random.

Post-experiment, the whiteness levels of both groups will be compared to analyze the gel's effect.

For true randomness in the experiment, options 3, 5, and 6 are applicable.

(b)

In order for the experiment to be double-blind, the evaluators analyzing the whiteness, as well as the participants, must not know which individuals were given the whitening gel versus the placebo.

Answer:

Response: C

Step-by-step explanation:

Assuming a maximum rental duration of 8 days, if we apply this to the equation, Happy Harry's Rentals costs $500, while Smilin' Sam's charges $600. Therefore, for the 7th and 8th days, Happy Harry's Rentals is a better option, while Smilin' Sam's is preferable for the first six days.

Response:

2/9 = 0.22

Clarification:

There are two ways to select the first number that is odd and less than 5: 1 and 3.

For each of these, the second number drawn can be any of the values from 1 to 9, giving us a total of 18 options.

Out of these, the only pairs that result in a sum less than 5 are (1,1), (1,2), (1,3), and (3,1). Thus we have 4 combinations from the total of 18:

4/18 = 2/9 = 0.22

Answer:

Part A. At least 6 hours

Part B. In less than 2.5 hours, Elijah will fall behind Mercedes

Part C. In over 2.5 hours, Elijah will lead Aubrey

Step-by-step explanation:

D = distance

v = speed

t = time

Formula connecting D, v, and t:

Part A.

Steve's speed:

Distance: a minimum of 21 miles

Time: unknown, so

It would require Steve a minimum of 6 hours to traverse at least 21 miles on Day 1.

Part B.

Mercedes's speed:

Elijah's speed:

Elijah's Distance walked: miles

Mercedes's Distance walked: miles

Time: x hours

Mercedes is 2 miles ahead, therefore

Elijah will trail behind until

In 2.5 hours, Elijah will close the gap on Mercedes, and in less than 2.5 hours, Elijah will trail behind her.

Part C.

Aubrey's speed:

Elijah's speed:

Elijah's Distance walked: miles

Aubrey's Distance walked: miles

Time: x hours

At the beginning of Day 3, Elijah starts from Mile 42, while Aubrey begins at Mile 42.5.

Elijah will be ahead of Aubrey when

In 2.5 hours, Elijah will surpass Aubrey, and after more than 2.5 hours, Elijah will outpace Aubrey.