Answer:
The radius of the pie is 6.17 in.
Step-by-step explanation:
The formula for arc length as a function of radius is
s = r·Ф, where Ф is the central angle in radians.
Here we know that the arc length is 7.85 in. Assuming that the whole pie has been cut into 8 equal pieces, the central angle of one such piece is
2π / 8, or π /4 (radians).
thus, s = r·Ф, solved for r, is r = s/Ф
and in this instance r = (7.85 in)/(π/4). Evaluating this, we get:
r = 6.17 in
The radius of the pie is 6.17 in.
Answer:
What's the question?
Step-by-step explanation:
Answer: D
I just took the test and the answer is D.
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
