Answer:
P(Y ≥ 15) = 0.763
Step-by-step explanation:
Given that:
Mean =135
standard deviation = 12
sample size n = 50
sample mean
= 140
Suppose X is the random variable that follows a normal distribution which represents the weekly supermarket expenses
Then,

The probability that X is greater than 140 is :
P(X>140) = 1 - P(X ≤ 140)



From z tables,


Similarly, let consider Y to be the variable that follows a binomial distribution of the no of household whose expense is greater than $140
Then;


∴
P(Y ≥ 15) = 1- P(Y< 15)
P(Y ≥ 15) = 1 - ( P(Y=0) + P(Y=1) + P(Y=2) + ... + P(Y=14) )

P(Y ≥ 15) = 0.763
Step-by-step explanation:
Here's the first question and how to solve the second.
So the first business start with 250, that's your b in slope.
y = mx + b
y = mx + 250
Now, they charge 14 an hour so that's your m.
y = 14x + 250
x is the number of hours it takes.
The second business is straight up 22 per hour, so it's just y = mx, where b is 0.
y = 22x VS y = 14x + 250
Try plugging in different numbers and seeing how much it take to level out!
The slope of the graph is 1/2