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.
Which of the following numbers will replace the question mark (?) in the given series?
11, 22, 25, ?, 105, 630
'PC NA VU' can be a code of which of the following?
Six persons named P, Q, R, S, U and V are sitting in a straight line, all facing north direction. Each one of them belongs to one of six different citie...
L is the wife of Q. P is the mother of M. J is the father of L. M is the sister of H. J is the husband of H. How is P related to L?
Replace the question mark with an option that follows the same logic applied in the first pair.
62:12::74: ?
In a certain code language, 'LIKE' is coded as '1576' and 'LINK' is coded as '6581'. What is the code for 'E' in the given. code language?
Change the question mark with the option that follows the applied logic in the first pair.
J : P :: M : ??
What will come in place of the question mark (?) in the following equation if ‘+’ and ‘–’ are interchanged and ‘×’ and ‘÷’ are inter...
Two statements are given, followed by two conclusions numbered I and II. Assuming the statement to be true, even if they seem to be at variance with co...
Which of the following interchange of numbers (not digits) would make the given equation correct?
14 × 4 ÷ 10 + 10 – 20 = 2
Relevant for Exams:
