Question

There are 5 red, 6 yellow and 4 green balls in a box. A ball is selected at random from the box. What is the probability of selecting : (i)a yellow ball (ii) a red ball (iii) not a green ball​

Answer 1

Given :-

No. of red balls = 5

No. of yellow balls = 6

No. of green balls = 4

To Find :-

The given probability

Solution :-

No. of possible outcomes = 5 + 6 + 4 balls

= 15 balls

i) No. of favourable outcomes = No. of yellow balls = 6 balls

${\sf{Probability\: =\: {\dfrac{No.\: of\: favourable\: outcomes}{No.\: of\: total\: possible\: outcomes}}}}$

${\sf{\implies\: Probability\: =\: {\dfrac{6}{15}}}}$

Therefore probability for yellow balls is 6/15

ii) No. of favourable outcomes = No. of red balls = 5 balls

${\sf{Probability\: =\: {\dfrac{No.\: of\: favourable\: outcomes}{No.\: of\: total\: possible\: outcomes}}}}$

${\sf{\implies\: Probability\: =\: {\dfrac{5}{15}}}}$

${\sf{\implies\: Probability\: =\: {\dfrac{1}{13}}}}$

Therefore probability for red balls is 1/3

iii) No. of balls excluding green = 15 - 4 = 11

=> No. of favourable outcomes = 11

${\sf{Probability\: =\: {\dfrac{No.\: of\: favourable\: outcomes}{No.\: of\: total\: possible\: outcomes}}}}$

${\sf{\implies\: Probability\: =\: {\dfrac{11}{15}}}}$

Therefore probability for no green balls is 11/15

Answer 2

$\red\bigstar$ Answer:

• Probability for yellow balls is 6/15

• Probability for red balls is 1/3

• Probability for no green balls is 11/15

$\pink\bigstar$Given :

• Number of red balls = 5

• Number of yellow balls = 6

• Number of green balls = 4

$\green\bigstar$To Find :

Probability of selecting :

1. A yellow ball
2. A red ball
3. Not a green ball

$\blue\bigstar$ Solution :

Number of possible outcomes

= (5 + 6 + 4) balls

= 15 balls

1.

Number of favourable conditions

= Number of yellow balls

= 6 balls

${\tt\green{Probability\: =\: {\dfrac{Number\: of\: favourable\: conditions}{Total \: number\: of\: possible\: outcomes}}}}$

${\tt{\implies\: Probability\: =\: {\dfrac{6}{15}}}}$

$\therefore$ Probability for yellow balls is 6/15

2.

Number of favourable conditions

= No. of red balls

= 5 balls

${\sf\pink{Probability\: =\: {\dfrac{Number\: of\: favourable\: conditions}{Total \: number\: of\: possible\: outcomes}}}}$

${\sf{\implies\: Probability\: =\: {\dfrac{5}{15}}}}$

${\sf{\implies\: Probability\: =\: {\dfrac{1}{13}}}}$

$\therefore$ Probability for red balls is 1/3

3.

Number of balls excluding green

= 15 - 4

= 11

Here,

Number of favourable conditions = 11

${\tt\blue{Probability\: =\: {\dfrac{Number\: of\: favourable\: outcomes}{Total \: number\: of\: possible\: outcomes}}}}$

${\tt{\implies\: Probability\: =\: {\dfrac{11}{15}}}}$

$\therefore$ Probability for no green balls is 11/15

$\blue\bigstar$ Concept Used:

• ${\sf\red{Probability\: =\: {\dfrac{Number\: of\: favourable\: conditions}{Total \: number \: of\: possible\: outcomes}}}}$