Area shaded = Area big circle- Area of small circle;
200 pi= pi•(2x)^2 -pi•6^2;
200pi= pi•4x^2 -pi•36;
200pi=pi•4(x^2 -9) divide both sides by 4pi;
50=x^2 -9; So x=sqrt(59)~7.68cm
900 x 8= 7200 is your answer
Answer: 
Step-by-step explanation:
The formula for area of a triangle is 
Now we have to isolate for w.
First multiply by the 2 which is the reciprocal of 1/2 to cancel it out.

Now divide by h to isolate w.
2/3 is your answer to the question
Answer:
A1) 125
A2) 47.5%
B) 30
Step-by-step explanation:
Remember 'of' in this sentence means times(*). % shows a certain number/100.
a1) 48% 'of' what number is 60?
(let unknown number be x)
48/100 *x=60
Solve the equation, and the answer is x=125
a2) what percentage 'of' 120 is 57?
(let the unknown percentage be x)
(x/100)*120=57
x=47.5%
b) 24 students= 80% of the total number of students
1%=24/80
100% of the total number of students=30
So, there are total of 30 students