AI Mentor

Check Your IQ

Free Expert Demo

Try Test

Courses

Dropper NEET Course Dropper JEE Course Class - 12 NEET Course Class - 12 JEE Course Class - 11 NEET Course Class - 11 JEE Course Class - 10 Foundation NEET Course Class - 10 Foundation JEE Course Class - 10 CBSE Course Class - 9 Foundation NEET Course Class - 9 Foundation JEE Course Class -9 CBSE Course Class - 8 CBSE Course Class - 7 CBSE Course Class - 6 CBSE Course

Offline Centres

The probability of selecting a red ball at random from a jar that contains only red, blue and orange balls is $\frac{1}{4}$ . The probability of selecting a blue ball at random from the same jar is $\frac{1}{3}$ . If the jar contains 10 orange balls, find the total number of balls in the jar.

see full answer

Your Exam Success, Personally Taken Care Of

1:1 expert mentors customize learning to your strength and weaknesses – so you score higher in school , IIT JEE and NEET entrance exams.

An Intiative by Sri Chaitanya

answer is A.

(Unlock A.I Detailed Solution for FREE)

Best Courses for You

JEE

NEET

Foundation JEE

Foundation NEET

CBSE

Detailed Solution

Given that, the probability of selecting a red ball at random from a jar that contains only red, blue, and orange balls is

\frac{1}{4} .

For an event A , the probability of an event P(A) is,

P (A) = \frac{Number of favorable outcomes}{Total number of outcomes}

The probability of selecting a blue ball at random from the same jar is

\frac{1}{3}

and the jar contains 10 orange balls.
Let the total number of balls be x .
Therefore, the probability that the randomly drawn ball is a red ball is,

P (A) = \frac{Number of red balls}{Total number of balls}

\Rightarrow \frac{1}{4} = \frac{Number of red balls}{x}

Number of red balls

= \frac{x}{4}

The probability that the randomly drawn ball is a blue ball is,

P (B) = \frac{Number of blue balls}{Total number of balls}

\Rightarrow \frac{1}{3} = \frac{Number of blue balls}{x}

Number of red balls

= \frac{x}{3}

Since the total number of balls is x ,

\Rightarrow \frac{x}{4} + \frac{x}{3} + 10 = x

\Rightarrow \frac{3 x + 4 x}{12} + 10 = x

\Rightarrow 5 x = 120

\Rightarrow x = 24

The total number of balls is 24.
Hence, option 1 is the correct answer.

Watch 3-min video & get full concept clarity

courses

No courses found

Result Producing online coaching for JEE/NEET of south India

Largest All India Test Series for JEE/NEET

Best Online Course for IIT JEE

Best Online Course for NEET

Best Online Course for CBSE

Ready to Test Your Skills?

Check your Performance Today with our Free Mock Test used by Toppers!

Take Free Test

Get Expert Academic Guidance – Connect with a Counselor Today!