Question

Find the area of the circle to the nearest tenth, if n=3.14 and a=5in.

a.78.5
b.69.4
c.31.5
d.47.5

Answer 1

Answer:

78.50

Explanation:

if the Radius(not area) is 5, you would do this equation

A=πr^2

as in area=pi x radius^2

so you would simplify this into

A=(3.14)(5)^2

so then you would square 5 which becomes 25.

the problem should look like this:

A=(3.14)(25)

you would then multiply 3.14 by 25 which equals 78.50 or

A=78.50

then you would round to the nearest tenth and since 0<5 it would be 78.5 or

A=78.5

Answer 2

For this case we have by definition that the area of the circle is given by:

$A = \pi * r ^ 2$

We have as data that the radio is given by:

$r = 5 \ in$

We use $\pi = 3.14$

So:

$A = 3.14 * 5 ^ 2\\A = 3.14 * 25\\A = 78.5 \ in ^ 2$

Answer:

$A = 78.5 \ in ^ 2$

Option A