Order operations 3 + 11 - 3 x 17 please show your work
2 answers:
You might be interested in
Answer:
$21.2
Step-by-step explanation:
From the problem given, we express them as algebra so that we can easily solve;
the total charge on a call greater than 120min is given as;
120x + y(n - 120) = total cost of call
where n is the number of minutes which is greater than 120;
- Ethan paid $26.80 for 175 mins
n = 175min here;
120x + y(175 - 120) = 26.80
120x + 55y = 26.80 ----- (I)
- $32.40 for 210 minutes
n = 210min
120x + y(210 - 120) = 32.4
120x + 90y = 32.4 ----- (II)
Now let us solve both equations for y and x;
120x + 55y = 26.80 ----- (I)
120x + 90y = 32.4 ----- (II)
subtract the two equations;
90y - 55y = 32.4 - 26.8
35y = 5.6
y = = 0.16cents
then x;
120x = 26.8 - 55y from equation I
120x = 26.8 - 55(0.16)
120x = 18
x = = 0.15cents
Find the cost of 140min of talk time;
n =140min;
= 120(0.15) + 0.16(140 - 120)
= 18 + 0.16(20)
= 18 + 3.2
= $21.2
Answer:
7 reservoirs
Step-by-step explanation:
1 yards = 3 feet => 3.5 yards = 10.5 feet
To determine how many numbers of reservoirs to reserve 90000, we first need to determine the capacity of each reservoirs (how much liquid one reservoir can contain) - which is equal to the volume.
The formula to calculate the volume of a circular cylinder is:
- <em>Volume of cylinder = Area of base x Height </em>
<em />
The base of this cylinder is a circle with radius equal to 4 feet. ()
=> The are of the base is = = 3.14 x 4^2 = 50.24 feet square
=> The volume of cylinder = Area of base x Height
=> The volume of one cylinder = 50.24 x 10.5 = 527.52 Cubic foot
We have: 1 cubic foot = 28.317 liters
=> 1 liter = 1/28.317 cubic foot
=> 90000 liters equal to: 90000/28.317 = 3,178.303 cubic foot
The number of reservoirs needed to contain 90000 liters of liquid is:
3,178.303/527.52 = 6.025
=> So that it needs 7 reservoirs to store all 90000 liters of liquid.