a) Let R,B,G denote the number of red,blue and green marbles respectively. let T be the total number of marbles.
According to the given problem,
T/6 = R => T =6R ....(1) ,
B = G/4 => G = 4B.....(2),
G-R=15 => R = G - 15....(3)
R+B+G=T ...(4)
substituting (1) in (4) we get, R + B + G = 6R => B + G = 5R, , substituting R from eqn.(3), we get B + G = 5(G - 15)
putting G= 4B we get, => B + 4B = 5 (4B - 15)
=> 5B = 5(4B - 15) => B = 4B - 15 => 3B = 15 => B=5
putting B=5 in (2), we get G=20
puting G=20 in (3) we get R = 20-15 = 5
Therefore there are 5 red marbles, 20 green marbles and 5 blue marbles.
b)
Abag contains red, geen. and blue marties Ono-sldhofthe mables are red, thern aroǐas many blue maties...
A bag contains 7 red marbles, 6 blue marbles, and 8 green marbles. A randomly drawn marble is blue. O on la
7A bag contains 6 red marbles, 3 blue marbles, and 4 green marbles. If five marbles are randomly selected from the bag, what is the probability that (a) exactly three are red marbles. (b) there is no red marble. (Hint: use combinations)