What is the perimiter of this 1/4 circle

A. 7.85in
B. 12.9in
C. 17.9in
D. 31.4in

Explanation:

A full circle of radius 5 inches would have a perimeter or circumference of...

C = 2*pi*r

C = 2*3.14*5

C = 31.4

This value is approximate because pi = 3.14 is approximate.

The distance around a full circle with radius 5 inches is roughly 31.4 inches, but we only want a quarter of this. Therefore, the distance around the curved portion of the quarter circle is roughly C/4 = (31.4)/4 = 7.85 inches.

Choice A would be the answer if your teacher only cared about the curved portion. However, don't forget about the straight line portions that also make up the quarter circle. Choice A might have been put there as a trick answer.

We'll add on the two copies of the radius 5 inches to get a total perimeter of 5+5+7.85 = 10+7.85 = 17.85 = 17.9 inches, which points to choice C as the answer.

Side note:

If we used a more accurate version of pi, say the version stored in your calculator, then the perimeter is roughly

5+5+(2*pi*5)/4 = 17.8539816339744

Rounding to the nearest tenth leads to the same answer of 17.9 inches

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.

explanation:

step-by-step explanation: