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# Ex.15.1 Q1 Probability Solution - NCERT Maths Class 9

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## Question

In a cricket match, a batswoman hits a boundary $$6$$ times out of $$30$$ balls she plays. Find the probability that she did not hit a boundary.

Video Solution
Probability
Ex exercise-15-1 | Question 1

## Text Solution

What is known?

Total number of balls played and number of times the batswoman hits boundary.

What is unknown?

Probability of the batswoman not hitting a boundary.

Reasoning:

If the batswoman hits a boundary $$6$$ times out of $$30$$ balls then she will not hit a boundary in the remaining $$24$$ balls.

The empirical probability $$P(E)$$ of an event $$E$$ happening, is given by:

\begin{align}{P}({E})=\frac{ \begin{bmatrix} \text { Number of trials in which }\\ \text{the event happened } \end{bmatrix} }{ \begin{bmatrix} \text { The total number} \\ \text{of trials } \end{bmatrix} }\end{align}

Steps:

Number of balls played $$= 30$$

Number of balls the batswoman hits boundary $$= 6$$

Number of balls the batswoman does not hit a boundary $$= 30 - 6 = 24$$

$$P$$(bats - woman does not hit the boundary)
\begin{align} & = \frac{ \begin{bmatrix}\text{Number of times the bats-woman}\\ \text{ does not hit the boundary} \end{bmatrix}} {\text{Number of balls played}} \\ & = 24/30 \\ &= 4/5 \end{align}

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