Hey,
So we have to solve this in multiple steps. Step 1 is to find the circumference of the semi-circle and multiply by three since there are three. Step 2 would be to find the perimeter of the rectangle. Step 3 would be to add those two together.
Step 1: To find the circumference of the semicircle use the formula pi (3.14) times radius (8 ÷ 2 = 4) times 2. After that we will divide by two since there is only half. After that we will multiply that answer by three.
C = 3.14 x 4 x 2
C = 12.56 x 2
C = 25.12
C = 25.12 ÷ 2
C = 12.56
Perimeter = 12.56 x 3 = 37.68
Step 2: To find the perimeter of the rectangle/square add all the sides (8).
Perimeter = 8 + 8 + 8 + 8 = 32
Step 3: Now add the two previous answers to get the final perimeter.
37.68 + 32 = 69.68
Final Answer: 69.68
Hope this helped!
Cheers,
Izzy
John bought 18 erasers.
Explanation: He has $6.00
He spends $3.12 on notebooks
Then you do $6.00 - $3.12 and you get $2.88
If it’s ¢16 per eraser and he has no money left over after buying erasers than you would divide $2.88 by $0.16 which turns into 288 divided by 16 which comes out to 18.
Therefor John bought 18 erasers.
Part 1:
Given that the length of the chord is 18 cm and the chord is midway the radius of the circle.
Thus, half the angle formed by the chord at the centre of the circle is given by:

Now,

Therefore, the radius of the circle is
10.4 cm to 1 d.p.
Part 2I:
Given that the radius of the circle is 10 cm and the length of chord AB is 8 cm. Thus, half the length of the chord is 4cm. Let the distance of the mid-point O to /AB/ be x and half the angle formed by the chord at the centre of the circle be θ, then

Now,

Part 2II:
Given that the radius of the circle is 10cm and the angle distended is 80 degrees. Let half the length of chord CD be y, then:

Thus, the length of chord CD = 2(6.428) = 12.856 which is approximately
12.9 cm.