find the area and perimeter of a semi circle of diameter 30.8cm
Answers
Answer:
Step-by-step explanation:A
=
π
r
2
and
C
=
2
π
r
,
where
A
is the area of the circle,
C
is the circumference (or perimeter), and
r
is the radius.
Also,
d
=
2
r
, where d is diameter.
Now, plug in
10
cm (the diameter) into this equation to find the radius of the given circle (as
d
).
d
=
2
r
(
10
)
=
2
r
r
=
5
cm
Now, you can use the radius that you found and the first two equations that I mentioned to find the area and perimeter of the circle.
A
=
π
r
2
A
=
π
(
5
cm
)
2
C
=
2
π
r
C
=
2
π
(
5
cm
)
Now, you can enter this into your calculator, where
π
is about
3.14
.
After doing so, you should get the two following numbers:
A
=
78.5
cm
2
C
=
30.9
cm
These are your two answers!
I hope that helped!
Answer:
radius = 308/10 = 154 /5 cm
now , we know that the area of circle is pi r^2
since in case of semi circle area is divided by 2 we get .........
area = pi × r^2 /2
= 22/7 × 154/5 × 154/5 | 2
= 22× 154 ×154 / 7 × 5×5×2
= 22 ×22× 77/ 5 ×5
= 37268 /25
= 1490.72 cm^2
HERE
perimeter = pi × r = 22/7 × 154/5 = 22×22/5 = 484/5 cm = 96.8 cm