Answer:
Justin worked as a babysitter 8 hours and worked as a lifeguard 2 hours last week
Step-by-step explanation:
Let
x ----> number of hours worked as a babysitter last week
y ----> number of hours worked as a lifeguard last week
we know that
----> equation A
----> equation B
Solve the system by substitution
Substitute equation B in equation A

solve for y



Find the value of x

therefore
Justin worked as a babysitter 8 hours and worked as a lifeguard 2 hours last week
Answer:
The following are the answer to this question:
Step-by-step explanation:
In the given question the numeric value is missing which is defined in the attached file please fine it.
Calculating the probability of the distribution for x:

The formula for calculating the mean value:




use formula for calculating the Variance:
![\to \bold{\text{Variance}= E(X^2) -[E(X)]^2}](https://tex.z-dn.net/?f=%5Cto%20%5Cbold%7B%5Ctext%7BVariance%7D%3D%20E%28X%5E2%29%20-%5BE%28X%29%5D%5E2%7D)

calculating the value of standard deivation:
Standard Deivation (SD) =

Answer:
$280 dollars
Step-by-step explanation:
When they were leaving

When they returned home, they brought 196 Euros.

They brought back $280 dollars to the United States.
Answer:
9 feet
Step-by-step explanation:
Given:
The border of the garden is a right angled triangle.
Two lengths are given as 12 ft and 15 ft.
Let the length of the shortest timber be 'x' feet.
Now, in a right angled triangle, the longest length is called the hypotenuse.
As 15 feet is the largest length, it is the hypotenuse of the triangle. Now, applying Pythagoras theorem, we get:

The negative value is neglected as length can never be negative.
Therefore, the length of the shortest timber is 9 feet.
8mm to 2cm is the same as 8mm to 20mm
8 : 20 simplifies to 2 : 5
3.25cm ÷ 5 = 0.65cm
0.65 x 2 = 1.3cm
Your answer is 1.3cm