A) 512 | B) 1024 |

C) 625 | D) 20 |

Explanation:

First letter can be posted in 4 letter boxes in 4 ways. Similarly second letter can be posted in 4 letter boxes in 4 ways and so on.

Hence all the 5 letters can be posted in = 4 x 4 x 4 x 4 x 4 = 1024

A) 25200 | B) 25000 |

C) 25225 | D) 24752 |

Explanation:

Number of ways of selecting (3 consonants out of 7) and (2 vowels out of 4)

=( ) = ( ) = 210.

Number of groups, each having 3 consonants and 2 vowels =210

Each group contains 5 letters.

Number of ways of arranging 5 letters among themselves = 5! = (5 4 3 2 1)=120.

Required number of words = (210 120) = 25200.

A) 15 | B) 20 |

C) 5 | D) 10 |

Explanation:

Since each number to be divisible by 5, we must have 5 0r 0 at the units place. But in given digits we have only 5.

So, there is one way of doing it.

Tens place can be filled by any of the remaining 5 numbers.So, there are 5 ways of filling the tens place.

The hundreds place can now be filled by any of the remaining 4 digits. So, there are 4 ways of filling it.

Required number of numbers = (1 5 4) = 20.

A) 205 | B) 194 |

C) 209 | D) 159 |

Explanation:

We may have (1 boy and 3 girls)or(2boys and 2 girls)or(3 boys and 1 girl)or(4 boys).

Required number of ways = () + () + () + ()

= () + + +

= (24+90+80+15)

= 209.

A) Option A | B) Option B |

C) Option C | D) Option D |

Explanation:

Total number of flowers = (8+7+6) = 21.

Let E = event that the flower drawn is neither red nor green.

= event taht the flower drawn is blue.

n(E)= 7

P(E)=

A) Option A | B) Option B |

C) Option C | D) Option D |

Explanation:

Let S be the sample space. Then,

n(s) = number of ways of drawing 4 pearls out of 14

= ways = = 1001

Let E be the event of drawing 4 pearls of the same colour.

Then, E = event of drawing (4 pearls out of 5) or (4 pearls out of 4) or (4 pearls out of 5)

+ + = 5+1+5 =11

P(E) =

Required probability =