Fourty percent of all Americans drink bottled water more than once a week (Natural resources Defense Council, December 4, 2015). Suppose you have been hired by the Natural Resources Defence Council to investigate bottled water consumption in St. Paul. You plan to select a sample of St. Paulites to estimate the proportion who drink bottled water more than once a week. Assume the popluation proportion of St. Paulites who drink bottled water more than once a week is , the same as the overall proportion of Americans who drink bottled water more than once a week.
a. Suppose you select a sample of 540 St. Paulites. Show the sampling distribution of p-bar (to 4 decimals).
b. Based upon a sample of 540 St. Paulites, what is the probability that the sample proportion will be within 0.05 of the population proportion (to 4 decimals).
c. Suppose you select a sample of 220 St. Paulites. Show the sampling distribution of p-bar (to 4 decimals).
d. Based upon a smaller sample of only 220 St. Paulites, what is the probability that the sample proportion will be within 0.05 of the population proportion (to 4 decimals).
given that a ball is thrown verically upwards with an initial velocity. we know that the path is a trajectory as a parabola.
from graph we find that horizontal is in yards and vertical is in feet.
we have to find the coordinates of a
when ball is thrown upward, acceleration due to gravity is -32 ft/s^2
since height = s=+h0
we get h0 as initial height.
but without any calculation from the graph we find out these coordinates as
x coordinate = 2.5(since in the middle of 0 and 5)
y coordinate = 10.5(since in the middle of 9 and 12)
they have the same angles.
in order for two triangles where you know the side lengths to be congruent, their sides must be in the same ratio at all times. if this s not satisfied, they are not similar. this means that kj / rs = kl / ts = jl / rt, or 15 / 12 = 20 / 16 = 25 / 20, or 5/4 = 5/4 = 5/4. this means that the two triangles are similar.
finally, this implies that they have the same angles.
this is a parallelogram so you find the total area using base times height.
bh = a
b = 6.5 + 2.5 = 9
h = 6
bh = 9(6)
a = 54 square yards
you now know that the total area is 54 yards. 20 times 3 equals 60 square yards so you know that you need at least 3 bags to cover the whole land area.