A car will hold 2 in front seat and 1 in rear seat. If among 6 persons 2 can drive, then number of w

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6.Permutation and Combination

medium

A car will hold $2$ in the front seat and $1$ in the rear seat. If among $6$ persons $2$ can drive, then the number of ways in which the car can be filled is

$10$

$20$

$30$

None of these

Solution

(b) Since $2$ persons can drive the car, therefore we have to select $1$ from these two. This can be done in $^2{C_1}$ ways. Now from the remaining $5$ persons we have to select $2$ which can be done in $^5{C_2}$ ways.

Therefore the required number of ways in which the car can be filled is $^5{C_2}{ \times ^2}{C_1} = 20$.

Standard 11

Mathematics

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hard

(JEE MAIN-2019)

Six ‘$+$’ and four ‘$-$’ signs are to placed in a straight line so that no two ‘$-$’ signs come together, then the total number of ways are

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easy

A group consists of $4$ girls and $7$ boys. In how many ways can a team of $5$ members be selected if the team has at least $3$ girls $?$

medium

If $P(n,r) = 1680$ and $C(n,r) = 70$, then $69n + r! = $

medium

A car will hold $2$ in the front seat and $1$ in the rear seat. If among $6$ persons $2$ can drive, then the number of ways in which the car can be filled is

Solution

Similar Questions

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