Her phrasing suggests that she would sell numerous water bottles and just a single iced tea. The accurate equation should be 1.25x + 1.49y = 100, as she may offer varying quantities of both.
We start with the following information:
p = probability = 0.12<span>
n = total number of students = 39 </span>
x = number of left-handers = 5<span>
u = mean = p * n = 4.68
σ = standard deviation = √(n*p*(1-p)) = √(39 * 0.12 * 0.88) =
2.03</span>
Finding the z score:
z = (x – u) / σ
<span>
z = (5 – 4.68) / 2.03
</span>
z
= 0.1576 = 0.16
<span>
</span>Applying standard tables for z gives the p value as:
p value = 0.5636 = 56.36%
Consequently, there is a 56.36% probability.
A proportion maintains a consistent ratio m/d
If m = 0.75d, then the m/d ratio translates to (0.75d)/d = 0.75
In this case, the ratio can be expressed as (.75d-2)/d = 0.75 - (2/d).
Thus, it is not proportional.
