Answer:
Stratified Random sampling
Step-by-step explanation:
When a random observations are selected from a number of individual groups in a particular population, the type of sampling technique is called Stratified Random sampling. Stratified Random sampling begins with the partitioning or splitting or a population into subgroups. A number of random selection are then made from each of the subgroups to form a collection of larger samples. This is different from the simple random sampling technique which makes random selection directly from a larger sample or population without prior partitioning of the population. The different grades of students represents the individual stratum from which random selections are made.
Z=kx, 30=8k, so k=30/8=15/4 and z=15x/4, so when x=4, z=15.
For this case we have the following expression:
h (t) = - 16t ^ 2 + 122t + 10
We look for the maximum of the function, for this, we derive:
h '(t) = - 32t + 122
We match zero:
-32t + 122 = 0
We cleared t:
t = 122/32
t = 3.8125 s
Then, the maximum height will be:
h (3.8125) = - 16 * (3.2185) ^ 2 + 122 * (3.2185) +10
h (3.8125) = 236.92 feet
Answer:
It takes the boulder to reach maximum height about:
t = 3.8125 s
the boulders maximum height is:
236.92 feet
Answer:
22.5° and 67.5°
Step-by-step explanation:
The sum of complementary angles equal 90°.
Given that one of the complementary angles is 3 times larger than the other, let "x" represent the other angle.
Thus, the following expression can be written to represent this case:
Solve for x
Divide both sides by 4
The measure of the complementary angles are:
x = 22.5°
3x = 3(22.5) = 67.5°
