Important for :

1

**There are 7 friends. If salaries of these friends are in order- **

**10K = S1 **≥** S2 **≥ **S3** ≥ **S4 **≥….. ≥ **S7 = 5K**

**Which of the following can’t be the average of these 7 friends.**

2

C

A + B = 2 × 20 = 40 yr B + C = 2 × 19 = 38 yr

C + A = 2 × 21 = 42 yr

On adding all three,

2 (A + B + C) = 40 + 38 + 42 = 120

⇒ A + B + C = 60

Similarly,

B = (A + B) – A = 40 – 22 = 18 yr

C = (C + A) – A = 42 – 22 = 20 yr

Note: In this question we can save 4-5 seconds by not calculating the age of the third person as with only the respective ages of A and B we can confirm the correct answer out of the given options.

Hence, option (C) is correct.

Hence, option (C) is correct.

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4

B

Price of milk in first year = Rs. 7.50 per litre.∴ Quantity of milk in first year = | 4080 | = 544 litres |

7.50 |

Price of milk in second year = Rs. 8.00 per litre.

∴ Quantity of milk in second year = | 4080 | = 510 litres |

8.00 |

Price of milk in third year = Rs. 8.50 per litre.

∴ Quantity of milk in third year = | 4080 | = 480 litres |

8.50 |

∴ Required average = | 3 × 4080 |

544 + 510 + 480 |

= | 12240 | = Rs. 7.98 |

1534 |

Hence, option (B) is correct.

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