Advertisements
Advertisements
प्रश्न
Choose the most appropriate option.
A boat travels upstream from A to B and back from B to A in 5 hours. The speed of the boat in still water is 8 km/hour and the speed of the current is 4 km/hour. Then, the distance from A to B is:
पर्याय
9 kms.
10 kms.
15 kms
12 kms
Advertisements
उत्तर
15 kms
Explanation:
Speed of the boat in still water = 8 km/hr
Speed of the current = 4 km/hr
∴ Speed downstream = 8 + 4 = 12 km/hr
Speed upstream = 8 − 4 = 4 km/hr
Let the distance between A and B be x.
Then,
`"x"/12+"x"/4=4` `("x"+3"x")/12=5`
`∴(4"x")/12=5`
`∴"x"=(12xx5)/4=15` km
APPEARS IN
संबंधित प्रश्न
Choose the most appropriate option:
A train which is moving at an average speed of 40 kmph, reaches its destination on time. When its average speed reduces to 35 kmph, then it reaches its destination 15 minutes late. The distance travelled by train is:
A man can row 14 km/hr in still water. ln, the stream flowing with the speed of 10 km/hr he takes 4 hours to move with the stream and come back. Find the distance he rowed the boat.
A student rides a bicycle at 8 kms/hr and reaches the school 2.5 minutes late. The next day he increases the speed to 10 kms/hr and reaches school 5 minutes early. How far is the school from his house?
120 men had food provision for 200 days. After 5 days, 30 men died of an epidemic. The food will last for further
Military camp is having the provisions for 300 people consuming 600 grams daily for 75 days. They are joined by 60 more men and the daily ration was reduced by 100 grams. How long will the provisions last approximately?
A train passes a 110 m long platform in 40 s and a boy standing on the platform in 30 s. The length of the train is
A train moving with uniform speed crosses a pole in 2 s and a 250 m long bridge in 7 s. Find the length of the train.
A goods train is 800 meters long and it is running at a constant speed of 60 km/per hour. If it takes 120 seconds to pass a bridge, then calculate the length of the bridge?
A man covered a distance of 280 km in 8 hours on a motorcycle. How much distance will be covered on a bicycle in 2 hours, if he rides the bicycle at `3/14` of the speed of the motorcycle?
Two cyclists start simultaneously from two points A and B, their destinations being B and A, respectively. After crossing each other, they precisely take 2 hours 33 minutes 36 seconds and I hour 26 minute 24 seconds respectively to reach their destinations. What is the ratio of the speed of the first to that of the second cyclist?
