Question

two taps can fill a tank in 12 minutes and 15 minutes respectively.if both the taps are opened simultaneosly and tap a is closed after 3 minutes,then how much time it take to fill the tank by tap b

Answer 1

reply me

Answer 2

Let the volume of tank be 1 unit.
Then in 1 min, tank A fills 1/12 of tank and B fills 1/15 of tank.

Does this help ?

Answer 3

i have done this step please tell me the next step

Answer 4

For first 3 mins, tank A will fill 3/12 of tank and B will fill 3/15 of tank
together, (3/12) + (3/15) of the tank has already been filled.

Now A is closed. We still need to fill 1 -[ (3/12) + (3/15) ] of the tank. B will do the job alone from here.

Answer 5

the answer i got is 11/20

Answer 6

Thats just the sum. o.O

Answer 7

ya .i got the answer 8 min 25 sec.thank u very much

Answer 8

Hmm, glad you did.
Sorry am not cross checking, if your logic is correct, then surely ans must be right. :)

Answer 9

a car covers a didtance of 715km at a constant speed.if the speed of car would have been 10km/hr more then it would have taken 2 hours less to cover the same distance.what is the original speed?

Answer 10

This will be an application of the d (distance) = r (rate or speed) X t (time).
Distance d is given as 715 kilometers (km)
Time is not given but will equal distance divided by speed which is also not given.
But it can be expressed as: t=715/speed. Now the new time would be expressed as:
715/(x+10) since the new speed is 10 km/hr faster (given). It is also further given that that this new time will be 2 hrs. less than the old time. Now you would set up an equation that says the same thing.