The surface area of a cylinder with circular bases of radius <em>r</em> and height <em>h</em> is equal to the sum of the areas of the two circular faces and the area of the rectangular lateral surface:
<em>A</em> = 2π<em>r</em>² + 2π<em>rh</em>
If you know the height <em>h</em>, then you can solve the quadratic equation for <em>r</em>.
1,000 x 2= 2,000
2,000/1=2,000
2,000 - 29 = 1,971
Answer:
A
Step-by-step explanation:
30% of 4
4÷100=0.04
0.04×30=1.2
Answer:
30 gallons of 20% acid solution should be mixed.
Step-by-step explanation:
Let x gallons of a 20% acid solution was mixed with 30 gallons of a 40% solution, to obtain a mixture of 30% acid solution.
Therefore, final volume of the solution will be (x + 30) gallons.
Now concept to solve this question is
20%.(x) + 40%.(30) = 30%.(x + 30)
0.20(x) + 0.40(30) = 0.30(x + 30)
0.20x + 12 = 0.30x + 9
0.30x - 0.20x = 12 - 9
.10x = 3
x = 
x = 30 gallons
Therefore, 30 gallons of the 20% acid solution should be mixed.
Answer:
I'm not sure but 19.2
Step-by-step explanation:
I'm sorry if its wrong