Advertisements
Advertisements
प्रश्न
Two taps can fill a cistern in 10 hours and 8 hours respectively. A third tap can empty it in 15 hours. How long will it take to fill the empty cistern, if all of them are opened together?
Advertisements
उत्तर
First tap can fill a cistern in 10 hours
Second tap can fill the cistern in 8 hours
Third tap can empty the cistern in 15 hours
∴ First tap's 1 hour's work = `1/10`
Second tap's 1 hour's work = `1/8`
and third tap's 1 hour's work = `1/15`
If all of them are opened together, then
heir one hour's work = `1/10 + 1/8 - 1/15`
`= (12 + 15 - 8)/120 = (27 - 8)/120 = 19/120`
∴ They can fill the cistren in =`120/19` hours
`= 6 6/19` hours
APPEARS IN
संबंधित प्रश्न
A and B working together can do a piece of work in 10 days B alone can do the same work in 15 days. How long will A alone take to do the same work?
A can do a piece of work in 4 days and B can do the same work in 5 days. Find, how much work can be done by them working together in:
- one day
- 2 days
What part of work will be left, after they have worked together for 2 days?
A train covers 51 km in 3 hours. Calculate its speed. How far does the train go in 30 minutes?
Rohit goes 350 km in 5 hours. Find:
(i) his speed
(ii) the distance covered by Rohit in 6.2 hours
(iii) the time taken by him to cover 210 km.
Nazar travelled 360 Km at the speed of 90 Km/hour. Find the time taken for his travel
These log boats do not go very far. If the wind is helpful, then travel about 4 km in one hour.
How long will they take to go a distance of 10 km?
These log boats do not go very far. If the wind is helpful, then travel about 4 km in one hour.
Guess how far you can go in one hour if you walk fast.
Look at the different types of boats.
Some boats have motors and go further into the sea. since they go far out they can catch more fish. These boats travel faster, at a speed of about 20 km in one hour.
How much time will they take to go 85 km?
A vehicle covers 240 km in 4 hours. What is its speed?
If a car travels at a constant speed of 45 km/h for 3 hours, what distance will it cover?
