Please take a look at this PDF document, and see problem 17. Because it is written into georgian languages i will translate it in english. problem is following we have two circle with common center and AB and CD diameters which intersects each -other at right angles. there is given two condition

A)  area of large circle is 10 sm^2
B) area of  small circle is 2 sm^2


for find area of darkened part of big circle which one is correct

1)first condition is enough  and second not
2.second is enough and first not
3.both are enough  but not   seperately
4.it is enough  each seperately
5.both conditions are not enough,there is necessary  additional  statement


and one question more .for my opinion because these diameters intersect at right angles then area of each small sector is 1/4 of each big darkened sectors.am i right? thanks

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