Answer:

Step-by-step explanation:
Let
x-----> the number of girls
y-----> the number of boys
we know that
-----> equation A

isolate the variable y
-----> equation B
Substitute equation B in equation A



It is negative 6
the least number is subtracted from the greatest number
Answer:
The probability that the sample proportion will be greater than 13% is 0.99693.
Step-by-step explanation:
We are given that a large shipment of laser printers contained 18% defectives. A sample of size 340 is selected.
Let
= <u><em>the sample proportion of defectives</em></u>.
The z-score probability distribution for the sample proportion is given by;
Z =
~ N(0,1)
where, p = population proportion of defective laser printers = 18%
n = sample size = 340
Now, the probability that the sample proportion will be greater than 13% is given by = P(
> 0.13)
P(
> 0.13) = P(
>
) = P(Z > -2.74) = P(Z < 2.74)
= <u>0.99693</u>
The above probability is calculated by looking at the value of x = 2.74 in the table which has an area of 0.99693.
Answer:
x = 7
Step-by-step explanation:
Given
5x - 1 - 2x = 20, that is
3x - 1 = 20 ( add 1 to both sides )
3x = 21 ( divide both sides by 3 )
x = 7