Abag contains 10 res marbles, 15 yellow marbles, 5 green marbles, and 20 blue marbles. five marbles are drawn from the bag. what is the approximate probability that exactly two of the five are blue

it is probably the graph on the bottom right.

geometry: triangles

solvers

lessons

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call the larger triangle abc

then the smaller triangle cde is similar to abc (all angles are equal, aaa).  

ab is the side that is 36, and we wish to find de, the side corresponding to ab

area_cde = area_abc - area_cde --> area_abc / area_cde = 2

let x=length of de

ratio of areas = (ratio of sides)^2

+2+=+%2836%2fx%29%5e2+

+2+=+1296%2fx%5e2+

++x%5e2+=+1296%2f2+=+648+

25.45584