Given:
A man walks for x hours at a speed of (x + 1) km/h and cycles for (x - 1) hours at a speed of (2x + 5) km/h.
Total distance travelled is 90 km.
To find:
The value of x.
Solution:
We know that,
A man walks for x hours at a speed of (x + 1) km/h, so walking distance is
km
The man cycles for (x - 1) hours at a speed of (2x + 5) km/h, so the cycling distance is
km
Now,
Total distance = 90 km
Time cannot be negative. So, the only possible value of x is 5.
Answer:
And then
C. 240
Step-by-step explanation:
Previous concepts
Analysis of variance (ANOVA) "is used to analyze the differences among group means in a sample".
The sum of squares "is the sum of the square of variation, where variation is defined as the spread between each individual value and the grand mean"
When we conduct a multiple regression we want to know about the relationship between several independent or predictor variables and a dependent or criterion variable.
If we assume that we have independent variables and we have
individuals, we can define the following formulas of variation:
And we have this property
If we solve for SSR we got:
(1)
And we know that the determination coefficient is given by:
We know the value os and we can replace SSR in terms of SSY with the equation (1)
And solving SSY we got:
And then
C. 240