Answer:
The number of heads observed is 121.14 heads
Step-by-step explanation:
The formula for the z-score of a proportion is given as follows;
Where:
= Sample proportion
p = Population success proportion = 0.5
q = 1 - p = 1 - 0.5 = 0.5
n = Number in of observation = 200
z = 2.99
Hence, we have;
Therefore;
= 0.6057
∴ The number of heads observed = 200 × 0.6057 = 121.14 heads.
let us assume that the first company the cab flat rate is 5$ and the cap driver charges 2$ per mile .for the second company the cab flat rate is 3$ and the cab driver charges 3$ per mile.
a. the company charges per ride at least 5$ and an extra 2$ per mile
b.the equation we will choose is slope intercept since we know the
y-intercept which is the cab flat rate .
y=mx+b
where
m :is the slope
b:is the y-intercept
y:total amount
x. is the milage
total amount=2x+5.
c.the slope will be 2$ which is the change in amount per mile.the y-intercept will be the cab's flat rate.
Let us start with assuming the amount of coffee worth $20 a pound to be "x" pounds.
Now she wants to mix "x" pounds of $20 coffee with 70 pounds of $90 coffee.
So the mixture would be (x + 70) pounds.
And the value of mixture would be = 20·x + (90)·(70) = (20x + 6300) dollars.
She want to sell this mixture at rate of $30 a pound. Her earning would be = 30·(x + 70) = (30x + 2100) dollars.
We know that the value of mixture would be equal to her earnings.
30x + 2100 = 20x + 6300
30x - 20x = 6300 - 2100
10x = 4200
x = 420
So, 420 pounds of $20 coffee would be used.
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