ANSWER
EXPLANATION
If y varies directly with x, we write the mathematical statement;
When we introduce the constant of proportionality k, then we write the equation,
If y is 2.5 when x is 5,then we have;
The equation of variation then becomes;
when x=14,
The square root of 144 is 12. So multiply 8.3333 by 12. You should get 99.9996.
Hey there! :D
The biggest thing to remember here is the similar triangles and their side lengths.
Okay, so we can separate these triangles into 3 similar triangles. Which, we only need to do that to two for a proportion, but if you were to have more variables, you could separate the triangles even more if you needed to.
We want to find two triangles that have "x" has a value of their side, so we can solve a proportion.
The bigger triangle, (the whole two triangles combine) and the smaller triangle on the left can be used to make a proportion.
On the smaller triangle:
We have 9 cm on the shorter side and x as the hypotenuse.
On the larger triangle:
We have x as the shorter side, and then 25 as the hypotenuse. (9+16)
Note: You have to flip the larger triangle upside down to make it a similar structure to the other two triangles. It is similar, you just have to flip it.
So, now we can make a proportion.
Now, cross multiply.
9*25= 225
x*x=
So, find the square root.
√225= 15
x= 15. I hope this helps!
~kaikers
Missing question: How many executives should be surveyed?
Solution:
Mean = 13 hours
SD = 3 hours
Confidence level = 95%
Mean viewing time within a quarter of an hour = 0.25 = 1.96*3/sqrt (N)
Where N = Sample population
N = {(1.96*3)/0.25}^2 = 553.19 ≈ 554
Therefore, 554 executives should be surveyed to yield such results.
