What do you mean what is UW ? There is no equation
<span>30 hours
For this problem, going to assume that the actual flow rate for both pipes is constant for the entire duration of either filling or emptying the pool. The pipe to fill the pool I'll consider to have a value of 1/12 while the drain that empties the pool will have a value of 1/20. With those values, the equation that expresses how many hour it will take to fill the pool while the drain is open becomes:
X(1/12 - 1/20) = 1
Now solve for X
X(5/60 - 3/60) = 1
X(2/60) = 1
X(1/30) = 1
X/30 = 1
X = 30
To check the answer, let's see how much water would have been added over 30 hours.
30/12 = 2.5
So 2 and a half pools worth of water would have been added. Now how much would be removed?
30/20 = 1.5
And 1 and half pools worth would have been removed. So the amount left in the pool is
2.5 - 1.5 = 1
And that's exactly the amount needed.</span>
We need to find the surface area and volume for each rectangular prism. Here are the formulas I'm going to plug each prism's measurements.
S.Area=2(lw+wh+lh)
Volume: lwh
Question 75:
Volume: 3×1×3=9 cm³
Surface Area= 2(3)+2(3)+2(9)=6+6+18=30 cm²
Question 76:
Volume: 6×2×5=60 ft.³
Surface Area: 2(12)+2(10)+2(30)=24+20+60=104 ft²
Question 77:
Volume: 4×2×6=48 m³
Surface Area: 2(8)+2(12)+2(24)=16+24+48=88 m²