A) 50 days | B) 48 days |

C) 47.5 days | D) 49 days |

Explanation:

50 men can build a tank in 40 days

Assume 1 man does 1 unit of work in 1 day

Then the total work is 50×40 = 2000 units

50 men work in the first 10 days and completes 50×10 = 500 units of work

45 men work in the next 10 days and completes 45×10 = 450 units of work

40 men work in the next 10 days and completes 40×10 = 400 units of work

35 men work in the next 10 days and completes 35×10 = 350 units of work

So far 500 + 450 + 400 + 350 = 1700 units of work is completed and

Remaining work is 2000 - 1700 = 300 units

30 men work in the next 10 days. In each day, they does 30 units of work.

Therefore, additional days required = 300/30 =10

Thus, total 10+10+10+10+10 = 50 days required.

A) 7000 | B) 21000 |

C) 14000 | D) 15000 |

A) ₹15000 | B) ₹14000 |

C) ₹21000 | D) ₹7000 |

A) 45,000 | B) 30,000 |

C) 35,000 | D) 40,000 |