Answer is B: 150
write two equations
r+s=190
4r+3s=720
solve by substitution
the get r=150 s=40
Answer:
The % increase is 7.179 but see the remark I made below. What I have given and what it could be is a rounding error. Less than 2 dollars error is not much when you are calculating something for someone just to show them how to do it.
Step-by-step explanation:
242,555 * x/100 = 259,970 Multiply by 100
242,555 * x = 259970 * 100
242,555 * x = 25997000 Divide by 242555
x = 24997000/242444
x = 107.179
That's the total increase.
What you want is 7.179%
If you take 7.179% of 242,555 and add it onto 242555 you should get 259,970
7.1797/100 * 242555 = 17413.02
17413.02 + 242555 = 259968.02
Why isn't it exact. I'm out just about 2 whole dollars. The reason is that the % isn't exact. It's only out to 3 decimal places which apparently is not enough. You can go over my numbers if you want more exactness us use something that is rounded to 7.180 if you like.
Equation for circumference is c = 2(pi)r
r = 1/2(d)
d = 20
So…. r = 1/2(20) = 20/2 = 10
Going back to circumference equation
c = 2(pi)(10) = 2(3.14)(10) = 62.8
Answer:
Manufacturers has to produce 63 DVD/Blu-Ray players to achieve a minimum cost of $644
Step-by-step explanation:
The cost equation is given as:
This is a quadratic equation in general form, which is:
Matching, we can say:
a = 0.04
b = -5
c = 800
The minimum occurs at 
and the minimum value would be to place that "x" value into the equation.
First, we find the minimum using values of a and b:
Plugging this into original, we get:
Rounding off to nearest whole number, we can say:
Manufacturers has to produce 63 DVD/Blu-Ray players to achieve a minimum cost of $644
