Question

a bag contains 80 red marbles,24 white marbles and few blue marbles find the number of blue marbles in the bag if the probability of getting a blue marble is 1/5

Answer 1

Dear student,
$$\begin{gathered} Letthenumberofbluemarblesbex \\ No.ofredmarbles=80 \\ No.ofwhitemarbles=24 \\ Totalno.ofmarbles=No.ofredmarbles+No.ofwhitemarbles+No.ofbluemarbles \\ =80+24+x \\ =104+x \\ Probabiliyofbluemarbles=\frac{Numberofbluemarbles}{Totalno.ofmarbles} \\ \Rightarrow \frac{1}{5}=\frac{x}{104+x} \\ \Rightarrow 104+x=5x \\ \Rightarrow 104=5x-x \\ \Rightarrow 104=4x \\ \Rightarrow \frac{104}{4}=x \\ \Rightarrow \boxed{x=26} \\ Thus,thenumberofbluemarblesinabagare26. \end{gathered}$$
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