Question
25 men can complete a piece of work in 13 days. One man
starts the work and after every day one more man joins the work and this continues till the work is completed. Then, in how many days will the work be completed?Solution
Let 1 day work of 1 man = 1 units So total work = 25 ×13 = 325 units Suppose after n days work is finished. So, 1 + 2 + ………… +n = 325 ⇒ (n(n+1))/2 = 325 n² + n – 650 = 0 n² + 26n – 25n – 650 = 0 n(n + 26 ) – 25(n + 26) = 0 (n - 25) (n + 26) ∴ n = 25 Hence, the work will be finished in 25 days.
Who has been appointed as the officiating Director General (DG) of CRPF in January 2025?
Which of the following planets is also called the "morning star" and the "evening star"?
Consider the following statements with respect to the sowing area of the crops -
I. According to data released by the Ministry of Agriculture & F...
- What is another term for skeletal muscles?
Prime Minister Narendra Modi has achieved the distinction of being the first world leader to accumulate how many YouTube subscribers?
Paris is the capital of which country?
Which among the following does not require a simple majority?
United Cup is related to which game?
Which state is hosting the 38th National Games for the first time?
- Which article of the Indian Constitution states that "The official language of the Union shall be Hindi in Devanagari script"?