Total age of 10 students = 150 years

Total age of 15 students = 240 years

Total age of 5 new students = 240 - 150 = 90 years

Average age of 5 new students = = 18 years

A) 11.8 | B) 12.9 |

C) 13.7 | D) 14.5 |

Explanation:

Let the present ages of Mahesh, Nilesh and Ramesh be k, l and m respectively.

k/l = 5/x ------ (1)

k = m - 18 ------ (2)

m + 9 = 47 ------ (3)

k - l = m ----- (4)

(3) => m = 47 - 9 = 38 years

(2) => k = 38 -18 = 20 years

(1) => 20/l = 5/x => l = 4x

(4) => 4x - 20 = 38

=> 4x = 58 => x = 14.5

A) 15 years | B) 16 years |

C) 18 years | D) 21 years |

Explanation:

Let the present ages of Arun and Harish be 4x and 3x years respectively.

Then, 4x + 6 = 26 => x = 5

Harish's age = 3x = 15 years.

A) 30 | B) 32 |

C) 38 | D) None |

Explanation:

Let Raju's age at the time of his marriage = X years

Then from given data

=> X + 8 = 6/5 X

X = 40.

Since got married 8 years ago, his present age = 48

His sister is 10 years younger => 48 - 10 = 38 years.

A) 10 yrs | B) 11 yrs |

C) 12 yrs | D) 13 yrs |

Explanation:

Let C's age be x years.

Then, B's age = 2x years.

A's age = (2x + 2) years.

(2x + 2) + 2x + x = 27

5x = 25 => x = 5

Hence, B's age = 2x = 10 years.

A) 19 years | B) 16 years |

C) 18 years | D) 20 years |

Explanation:

Present total age of the members = 26(5) = 130 years.

Present age of the youngest member = 10 years

Present total age of the remaining four members = 130 -10 = 120 years

Their average age at the time of the birth of the youngest member = = 30 - 10 = 20 years.