A door alarm works in 72 out of 100 cases.
surveillance camera works in 68 out of 100 cases.
The probability that method A is used = 72/100
The probability that method B is used = 68/100
Since both method are used we find the probability of A and B
Probability ( A and B) = 
* 
= 
Answer:
1 2/4, 2 3/4, 3, 3 2/4, 3 3/4
Step-by-step explanation:
fraction set up
The new parking lot must hold twice as many cars as the previous parking lot. The previous parking lot could hold 56 cars. So this means the new parking lot must hold 2 x 56 = 112 cars
Let y represent the number of cars in each row, and x be the number of total rows in the parking lot. Since the number of cars in each row must be 6 less than the number of rows, we can write the equation as:
y = x - 6 (1)
The product of cars in each row and the number of rows will give the total number of cars. So we can write the equation as:
xy = 112 (2)
Using the above two equations, the civil engineer can find the number of rows he should include in the new parking lot.
Using the value of y from equation 1 to 2, we get:
x(x - 6) = 112 (3)
This equation is only in terms of x, i.e. the number of rows and can be directly solved to find the number of rows that must in new parking lot.
Percent means per one-hundred....
48(p/100)=12
48p=1200
p=25%
So $12 off of a $48 item is 25% off.
Answer:
If the null hypothesis is true in a chi-square test, discrepancies between observed and expected frequencies will tend to be small enough to qualify as a common outcome.
Step-by-step explanation:
Here in this question, we want to state what will happen if the null hypothesis is true in a chi-square test.
If the null hypothesis is true in a chi-square test, discrepancies between observed and expected frequencies will tend to be small enough to qualify as a common outcome.
This is because at a higher level of discrepancies, there will be a strong evidence against the null. This means that it will be rare to find discrepancies if null was true.
In the question however, since the null is true, the discrepancies we will be expecting will thus be small and common.
