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) 68 & 44 | B) 64 & 48 |

C) 58 & 54 | D) 76 & 36 |

Explanation:

Given Karthik + Kalyan = 112

Given that when karthik is at the age of kalyan he is twice of Kalyan's age

i.e When he was 48 means Kalyan is at 24

=> Present age of Kalyan is 48

And that of Karthik is 112 - 48 = 64

A) 2 yrs | B) 4 yrs |

C) 3 yrs | D) 5 yrs |

Explanation:

29 x 2 = 58

20 x 3 = 60

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2 years

Therefore, the age of child is 2 years.

A) 32 yrs | B) 29 yrs |

C) 24 yrs | D) 27 yrs |

Explanation:

Total age seven persons = (26 x 7)years

Total age of the first three persons and the last three persons are (19 x 3) years and (32 x 3) years respectively.

Age of the person sitting in the middle of the row = 26 x 7 - 19 x 3 - 32 x 3 = 182 - 57 - 96 = 29 years.

A) 36 yrs | B) 38 yrs |

C) 40 yrs | D) 42 yrs |

Explanation:

Let the mother's present age be x years.

Then, the person's present age = 2/5 x years.

(2x/5 + 8) = 1/2 (x + 8)

2(2x + 40) = 5(x + 8) => x = 40.

A) 2 yrs | B) 12 yrs |

C) 18 yrs | D) 6 yrs |

Explanation:

Let Siya's age = x

Then Riya's age = 4x

But given Riya's age = 24

=> 4x = 24 => x = 6

Hence Siya's age = 6 yrs

=> The age difference = 24 - 6 = 18 yrs.