Holding a participant variable constant has the double advantage of (1) preventing the variable from becoming a confounding variable, and (2) reducing variance within groups. True or False

The provided statement is True.

Step-by-step explanation:

Holding a variable constant implies that there are no kind of relationship between the variables and the treatments.

Holding a participant variable constant has the double advantage:

(1) preventing the variable from becoming a confounding variable

(2) reducing variance within groups.

A confounding variable effects both the dependent and the independent variable remarking a relationship between the two.

Variation within group implies the difference caused by the individual values of each group.

Thus, the provided statement is True.

24

step-by-step explanation:

the graph shows 30% of students walk. 80 students were questioned, so the number that said they walk is

30% × 80 = 0.30 × 80 = 24

answer: 204

step-by-step explanation:

we are told that the revenue is

x⋅(4080−10x)=−10x^2+4080x

this is a quadratic function, so to maximize it we should find the x-value of its vertex. recall that the x-value of the vertex of the parabola ax^2+bx+c is given by the formula −b/2a.

so in this case, we have a=−10 and b=4080, so the x-value of the vertex is

−b/2a= −(4080)/2(−10)=204