SOLUTION: Point M is chosen random inside the big circle The radii of the small, middle and big circles are 4 cm, 7 cm, 10 cm respectively. What is the probability that a. Point M will be

Algebra ->  Real-numbers -> SOLUTION: Point M is chosen random inside the big circle The radii of the small, middle and big circles are 4 cm, 7 cm, 10 cm respectively. What is the probability that a. Point M will be       Log On


   



Question 1120214: Point M is chosen random inside the big circle The radii of the small, middle and big circles are 4 cm, 7 cm, 10 cm respectively. What is the probability that
a. Point M will be in the part C ?
b. Point M will be in the part B ?
c. Point M will be in the part A ?
image here:
http://homework.russianschool.com/resource?key=52745jgxxhu6i

Answer by ikleyn(52832) About Me  (Show Source):
You can put this solution on YOUR website!
.
Point M is chosen random inside the big circle The radii of the small, middle and big circles are 4 cm, 7 cm, 10 cm respectively.
What is the probability that
a. Point M will be in the part C ?
b. Point M will be in the part B ?
c. Point M will be in the part A ?
image here:
http://homework.russianschool.com/resource?key=52745jgxxhu6i
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a. Point M will be in the part C ?     The probability = the_area_of_the_circle_C%2Fthe_area_of_the_circle_A = %28pi%2A4%5E2%29%2F%28pi%2A10%5E2%29 = 16%2F100 = 0.16 = 16%

b. Point M will be in the part B ?     The probability = the_area_of_the_circle_B%2Fthe_area_of_the_circle_A = %28pi%2A7%5E2%29%2F%28pi%2A10%5E2%29 = 49%2F100 = 0.49 = 49%.

c. Point M will be in the part A ?     The probability = 1 = 100%.



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Comment from student:  thank you for helping with problem a.  however, i believe problem b & c are incorrect?
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My responce:   From my name  (referring to me)  say to the teachers in your school that they  INACCURATELY  formulate the problem.

The accurate formulation must say that B is the part of the middle circle which is not in  A.   From your post,  I read it differently.

Same for the part c.


I respect  "Russian Math school"  very much,  but in this case they are not correct . . .