Can someone check if my answers are right?

Leesygirl

New member
Joined
Mar 24, 2014
Messages
8
Question:

Given the diameter of a wall clock is 21cm, find, to the nearest two decimal places:

a. The circumference of the clock and
b. The area of the clock


Answers:

a. Circumference of a circle = πd
= 3.142 x 21
=65,98cm

b. Area = πr^2
= r= d/2 = 21/2
=3.142 x 10.5^2
=3.142 x 110.25
=346,40cm^2
 
to the nearest two decimal places

Circumference

65,98 cm

Area

346,40cm^2

The rounding seems a bit off, on each answer. I would not round Pi to three decimal places; I would use 3.14159

I get 65.97 cm for the circumference and 346.36 cm^2 for the area.

Thank you for showing your work.

:)
 
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