Answer:
20.
Step-by-step explanation:
P(5,3) = 5! / 3!
= (5*4*3*2*1) / (3*2*1)
= 20.
If you are finding the perimeter I believe you would just add up the four sides, getting 46
Answer:
If 11 oranges cost $2.35, then the cost of 18 oranges is $3.84.
Step-by-step explanation:
We have,
The number of oranges purchased varies directly as the price of the oranges.
If the cost of 11 oranges is $2.35.
It is required to find the cost of 18 oranges.
As their is direct relation between number and oranges and price.
So,
The cost of 1 orange is $
.
For finding the cost of 18 oranges, multiply 18 by $
such that,

So, If 11 oranges cost $2.35, then the cost of 18 oranges is $3.84.
Answer:

Step-by-step explanation:
We know that since angles in a triangle add up to 180º, the remaining angle must be 45º.
So the side with length
must be equal to the side with length
. That is:

Now, by Pythagoras:

Number of weekend minutes used: x
Number of weekday minutes used: y
This month Nick was billed for 643 minutes:
(1) x+y=643
The charge for these minutes was $35.44
Telephone company charges $0.04 per minute for weekend calls (x)
and $0.08 per minute for calls made on weekdays (y)
(2) 0.04x+0.08y=35.44
We have a system of 2 equations and 2 unkowns:
(1) x+y=643
(2) 0.04x+0.08y=35.44
Using the method of substitution
Isolating x from the first equation:
(1) x+y-y=643-y
(3) x=643-y
Replacing x by 643-y in the second equation
(2) 0.04x+0.08y=35.44
0.04(643-y)+0.08y=35.44
25.72-0.04y+0.08y=35.44
0.04y+25.72=35.44
Solving for y:
0.04y+25.72-25.72=35.44-25.72
0.04y=9.72
Dividing both sides of the equation by 0.04:
0.04y/0.04=9.72/0.04
y=243
Replacing y by 243 in the equation (3)
(3) x=643-y
x=643-243
x=400
Answers:
The number of weekends minutes used was 400
The number of weekdays minutes used was 243