Question
A boat makes a journey from point P to point Q and
return back in 6 hr 40 min. One way it travels with the stream and on the return it travel against the stream. Prdouct of speed in downstream and upstream is 216. If the speed of the stream increase by 2 km/hr, the return journey takes 7 hr 12 min. What is the speed of the boat in still water? The distance between P and Q is 48 km.Solution
Let the speed of boat in upstream = x km/hr Speed of boat in downstream = y km/hr Condition I: 48/x + 48/y = 20/3 ………..(1) Condition II: 48/(x – 2) + 48/(y + 2) = 36/5 ………..(2) Solving these equations: 48x + 48y = 20xy/3 …………(1) 48x + 48y = 36(x – 2)(y + 2)/3 …………(2) 100xy = 108(x – 2)(y + 2) ………(3) Product of speed boat in downstream and upstream = 216 xy = 216 ……(4) 100 x 216 = 108 (x – 2)(y + 2) 200 = 216 + 2x – 2y + 4 x – y = 6 …….(5) From eq (4) and (5), we got 216/y – y = 6 216 – y2 = 6y y2 + 6y – 216 = 0 (y + 18)(y – 12) = 0 Hence, y = 12 and x = 12 + 6 = 18 Speed of boat in still water = 1/2 (18 + 12) = 15 km/hr
Section 6 of the limitation Act is related to:
When there is a conflict between 2 statutes which rule to apply?
Arrest in cognizable cases can be______?
What is the nature of contract as laid down under the provisions of section 29 of the Indian Contract Act?
It is the duty of _______ to communicate the president about decisions of council of ministers
As per section 3 of the Competition Act no enterprise or association of enterprises or person or association of persons shall enter into any agreement ...
Which constitutional provision allows Parliament to legislate on a State List matter when two or more States request Parliament to do so?
Petty organised crime under Section 112 includes all of the following except:
Selling goods marked with a counterfeit property mark under Section 349 can be excused if the person proves:
Which of the following is not the part of right to freedom as enshrined in the Article 19 of the Constitution of India (As amended)?
Relevant for Exams:
