given: box containing 10 red, 20 blue and 30 green marbles

formula:

five marbles are drawn from the given box, total possible outcomes are ⁶⁰C₅

therefore n(S)=⁶⁰C₅

(i) let E be the event of getting all blue balls

n(E)= ²⁰C₅

(ii) let E be the event of getting at least one green

let E’ be the event of getting no green

E’= {(5B) (1R 4B) (2R 3B) (3R 2B) (4R 1B) (5R)}

5B=²⁰C₅

1R 4B=¹⁰C₁²⁰C₄

2R 3B=¹⁰C₂²⁰C₃

3R 2B=¹⁰C₃²⁰C₂

4R 1B=¹⁰C₄²⁰C₁

5R= ¹⁰C₅

P(E) =1-P(E’)