To start, the question is asking for surface area of a cylinder, meaning you will have to use this formula to find it: A=2πrh+2πr^2.
Since you already know that the diameter of the plastic cylinder is 4 marbles long, and each marble is 2 cm in diameter, you would multiply 4 and 2 to get that your diameter is 8 cm. However, since the surface area of a cylinder formula uses radius, you would simply divide 8 by 2 to get that the radius of the cylinder is 4 cm.
Now, since you already know that the height of the cylinder is equal to 10 marbles, multiply the amount of marbles by 2 to get that the height of the cylinder is 20 cm.
Now that you know the height and the diameter of the cylinder, plug the values into the formula: A=2π(4)(20)+2π(4)^2.
Assuming that pi is 3.14, simplify the equation as according to PEMDAS and you get that the area of plastic needed to make one cylinder is 602.88 cm squared
36-40= -4
36 subtracted by 40 equals negative 4
-4
<span>The distance between two cities is ninety miles, and a woman drives from one city to the other at a rate of 45 mph. At what rate must she return if the total travel time is three hours and forty minutes?
1st leg DATA:
distance = 90 mi ; rate = 45 mph ; time = d/r = 2 hrs.
</span><span>2nd leg DATA:
distance = 90 mi ; time = [3 2/3 - 2] = 1 2/3 hrs; rate = 90/(5/3) = 54 mph
Ans: 54 mph</span>
Answer:
angle A is 63 degrees,
angle B is 57 degrees
Step-by-step explanation:
first, let's create the equation. Pretty simple, because angles a and b become 120 degrees when added up, this this will become:
2x+3+2x-3=120
now, we make it simpler. In this case, just add up the numbers that we can add up. this eventually becomes:
4x=120
now, all we need to do is divide 120 by 4, which becomes 30. So, x=30.
substitute the 30 into the x in the original equation, and this becomes:
60+3+60-3=120
63+57=120
thus, angle A is 63 degrees, and angle b is 57 degrees.