Solve the problem. Use π = 3.14.
The Bay area of California was shaken by an earthquake on October 17, 1989. The epicenter was located at Loma Prieta. The diameter of the earthquake's horizontal waves that shocked the area measured about 120 miles. How many square miles were affected by this earthquake?
Blank Space__________square miles
To find the area affected by the earthquake, we need to calculate the area of a circle with a diameter of 120 miles.
The formula for the area of a circle is: A = πr^2, where A is the area and r is the radius.
Since the given diameter is 120 miles, the radius is half of that, which is 60 miles.
Plugging in the values into the formula, we get: A = 3.14 * 60^2.
Calculating the expression, we have: A = 3.14 * 3600.
Therefore, the area affected by the earthquake is approximately 11,304 square miles.
Question 2 options:
Is this statement true or false?
To find the circumference of a circle, multiply π by the diameter.
True.
Question 3 options:
Is this statement true or false?
Circumference is the distance around the outside of a circle.
True.
Find the area. Use π = 3.14.
3m
To find the area of a circle with a radius of 3m, we can use the formula A = πr^2.
Plugging in the values, we have A = 3.14 * 3^2.
Calculating the expression, we have A = 3.14 * 9.
Therefore, the area of the circle is approximately 28.26 square meters.
Question 5 options:
Solve the problem.
Find the circumference of a trampoline with a diameter of 14 feet. Use π = 3.14.
To find the circumference of a circle, we can use the formula C = πd, where C is the circumference and d is the diameter.
Given that the diameter of the trampoline is 14 feet, we can plug in the values into the formula:
C = 3.14 * 14
Calculating the expression, we have C = 43.96 feet.
Therefore, the circumference of the trampoline is approximately 43.96 feet.
Find the area. Use π = 3.14.
2cm
To find the area of a circle with a radius of 2cm, we can use the formula A = πr^2.
Plugging in the values, we have A = 3.14 * 2^2.
Calculating the expression, we have A = 3.14 * 4.
Therefore, the area of the circle is approximately 12.56 square cm.
Solve the problem.
Sand dollars are animals that live buried in the sand of shallow coastal waters. The thin circular body of a sand dollar is usually 2 to 4 inches wide. Find the area of a sand dollar that is 3 inches wide. Use π = 3.14.
To find the area of a sand dollar with a diameter of 3 inches, we can use the formula A = πr^2, where A is the area and r is the radius.
Since the given diameter is 3 inches, the radius is half of that, which is 1.5 inches.
Plugging in the values into the formula, we get: A = 3.14 * 1.5^2.
Calculating the expression, we have: A = 3.14 * 2.25.
Therefore, the area of the sand dollar is approximately 7.065 square inches.
Question 8 options:
Solve the problem.
Find the radius of a circle that has a circumference of 28.26 feet. Use π = 3.14.
To find the radius of a circle with a given circumference, we can use the formula C = 2πr, where C is the circumference and r is the radius.
Given that the circumference of the circle is 28.26 feet, we can plug in the values into the formula:
28.26 = 2 * 3.14 * r
Simplifying the equation, we have:
28.26 = 6.28r
Dividing both sides of the equation by 6.28, we get:
r = 4.5 feet
Therefore, the radius of the circle is approximately 4.5 feet.
Find the area. Use π = 3.14.
6m
To find the area of a circle with a radius of 6m, we can use the formula A = πr^2.
Plugging in the values, we have A = 3.14 * 6^2.
Calculating the expression, we have A = 3.14 * 36.
Therefore, the area of the circle is approximately 113.04 square meters.
Question 10 options:
Is this statement true or false?
The diameter of a circle is always greater than the radius of a circle.
False.
The diameter of a circle is always equal to 2 times the radius of a circle.