Subject
Quantitative Aptitude
Topic
Speed & Distance
The speeds of three cars are in the ratio 2 : 3 : 4 . the ratio of the times taken by these cars to travel the same distance is ( তিনটি গাড়ির গতির অনুপাত 2 : 3 : 4 । একই দূরত্ব অতিক্রমনে গাড়ি তিনটির প্রয়োজনীয় সময়ের সময়ের অনুপাত হবে- )
The speeds of three cars are in the ratio 2 : 3 : 4 . the ratio of the times taken by these cars to travel the same distance is ( তিনটি গাড়ির গতির অনুপাত 2 : 3 : 4 । একই দূরত্ব অতিক্রমনে গাড়ি তিনটির প্রয়োজনীয় সময়ের সময়ের অনুপাত হবে- )
ক)
2 : 3 : 4খ)
4 : 3 : 2গ)
4 : 3 : 6ঘ)
6 : 4 : 3Explanation
গাড়ি তিনটি গতিবেগ যথাক্রমে v 1 , v 2 , v 3 হলে v 1 : v 2 : v 3 = 2 : 3 : 4 ধরি, d দূরত্ব অতিক্রম করতে এদের যথাক্রমে t 1 , t 2 ও t 3 সময় লাগে । সময় = দূরত্ব/বেগ ∴ t 1 : t 2 : t 3 = (d/v 1 ) : (d/v 2 ) : (d/v 3 ) = (1/v) : (1/v 2 ) : (1/v 3 ) = 1/2 : 1/3 : 1/4 = 6 : 4 : 3 [ 2, 3, 4 এর ল.সা.গু. 12 দ্বারা প্রত্যেক আনুপাতিক রাশিকে গুণ করে ] ∴ নির্ণেয় অনুপাত = 6 : 4 : 3Related questions
A man takes twice as long to row a distance against the stream as to row the same distance in favour of the stream. The ratio of the speed of the boat (in still water) and the stream is:Speed of a boat in standing water is 9 kmph and the speed of the stream is 5 kmph. A man rows to a place at a distance of 105 km and comes back to the starting point. The total time taken by him is:two trains are moving in opposite directions at 60 km/hr and 90 km/hr. Their lengths are 1/10 km and 9 km respectively. The time taken by slower train to cross the faster train in seconds is -A man can row three-quarters of a kilometre against the stream in 11×(1/4) minutes and down the stream in 7×(1/2) minutes. The speed (in km/hr) of the man in still water is:In a 300 m race A beats B by 5 metre or 6 seconds. B's time over the course is -A boatman goes 2 km against the current of the stream in 1 hour and goes 1 km along the current in 10 minutes. How long will it take to go 5 km in stationary water?A boat covers a certain distance downstream in 1 hour, while it comes back in 1x(1/2) hours. If the speed of the stream be 3 kmph, what is the speed of the boat in still water?A man buys tk 20 shares paying 9% dividend. The man wants to have an interest of 12% on his money. The market value of each share is-