Calculate the circumference of the circles with the following dimensions. C = circumference
D = diameter
R = radius
PI = 3.14

1. D = 4 in D = 6 in D = 12 in
2. R = 2 ft R = 14 ft R = 12 ft
3. R = 9 ft R = 11 ft R = 7 ft
4. D = 10 ft R = 9 ft D = 13 ft
5. Application: Dana is planning to ride her bicycle around the circular race track and wants to know the distance. If the diameter of the track is 2 mile, how far is the distance around the race track?

Step-by-step explanation:

that is just calculator typing.

you really need help with that ?

the formula for the circumference of a circle is

2×PI×R

or correspondingly

PI×D

depending on whether we have the radius or the diameter (as the diameter is 2 times the radius).

now we just need to use the given numbers in these formulas and calculate.

1. 12.56 in 18.84 in 37.68 in

2. 12.56 ft 87.92 ft 75.36 ft

3. 56.52 ft 69.08 ft 43.96 ft

4. 31.4 ft 56.52 ft 40.82 ft

or maybe the middle of 4. should be D and not R ?

then it is 28.26 ft.

5. 6.28 miles

898.1666667

step-by-step explanation:

5389/6 = 898.1666667

54 kilometers per hour

step-by-step explanation:

according to rules:

1 km = 1000 meter

which means that 1 meter = 1/1000 km

1 hour = 3600 second [ as 1 hour = 60 min = 60 *60 seconds ]

which means that 1 second = 1/3600 hour

therefore, 1 kilometer/hour =

thus to convert 15 meter per second to kilometer per hour, we multiply 15 to 3.6 kilometer/hour.

15 meter/second=   which is the required answer.