Answer:
2 divided by 22 equals 0.55. 8 divided by 15 equals 0.53. So runner A had a greater average speed.
Step-by-step explanation:
Answer:
first you add the 2x and the 3x together then when you get your answer when you add them then you dived your answer and the 15 together
Step-by-step explanation:
hope this helps i didn't put the answers cause i didn't think you wanted them cause all you put was how do i find x
Answer:
$1.12
Step-by-step explanation:
One way to solve this problem is through an algebraic equation. Set up the equation like this, 
. This equation works because 3.28 is subtracted from 10, which represents how much was spent in total. Then, this is equal to 6x, which represents the total cost of six keys.
So, to solve first subtract 3.28 from 10, this gives you 6.72. Then, divide both sides by 6. This equals 1.12, which is the cost of each key.
Answer:
7.4. I BELIEVE...sorry if i did it wrong
Step-by-step explanation:
1 2/3 + 1 2/3 = 3.33333333
2 + 2 = 4
3.333333 + 4 = 7.333333
7.333333 rounded would be 7.4
Answer:
16,242. 7 cm^3.
Step-by-step explanation:
We need to cut off a square piece at the 4 corners of the cardboard.
Let the length of their edges be x cm.
The volume of the box will be:
V = height * width * length
V = x(100-2x)(40-2x)
V = x(4000 - 200x - 80x + 4x^2)
V = x(4x^2 - 280x + 4000)
V = 4x^3 + - 280x^2 + 4000x
Finding the derivative:
dV / dx = 12x^2 - 560x + 4000 = 0 ( when V is a maxm or minm.)
4(3x^2 - 140x + 1000) = 0
x = 37.86, 8.80.
Looks like x = 8.80 is the right value but we can check this out be looking at the sign of the second derivative:
V" = 24x - 560, when x = 8.8 V" is negative so this is a Maximum for V.
So the maximum volume of the box is when x = 8.8 so we have
V = 8.8(100-2(8.8)(40 - 2(8.8)
= 16,242. 7 cm^3.
