GATE2019 CE-2: GA-9

An oil tank can be filled by pipe $X$ in $5$ hours and pipe $Y$ in $4$ hours, each pump working on its own. When the oil tank is full and the drainage hole is open, the oil is drained in $20$ hours. If initially the tank was empty and someone started the two pups together but left the drainage hole open, how many hours will it take for the tank to be filled? (Assume that the rate of drainage is independent of the Head)


1. $1.50$
2. $2.00$
3. $2.50$
4. $4.00$
Part filled by pipe $X$ in $1$ hour $= \frac{1}{5}$  

Part filled by pipe $Y$ in $1$ hour $= \frac{1}{4}$  

Part emptied by drainage hole in $1$ hour $= \frac{1}{20}$  

  

Net part filled by pipes $X$ & $Y$ and when drainage hole is left open in $1$ hour $= \frac{1}{5} +\frac{1}{4} -\frac{1}{20} = \frac{2}{5}$  

  

So, the oil tank can be filled in $\dfrac{1}{\frac{2}{5}} = 2.5 \;\text{hours}$  

  

Correct Answer: $C$
It takes Okinawa Praise for single full charge is 6-8 Hrs hours answer: `1.00` amy takes an hour so she does
1/60 of yhe job per minute
father takes 30 mins so he does
1/30 of the job per minute
 
together they complete
1/60 + 1/30 per minute 
or 3/60 of the job per minute
 
(3/60)x = 1
x = 60/3
x = 20 minutes once you have accepted a booking, customers will have two hours to pick up the currency that they have ordered at your location. once the two hours are up, the booking will have expired. Hi my name is Keith from kl window doctor. All upvc should have a drainage holes face drained or concealed underneath and sometimes they get blocked which means you have to take each unit out and pour water out of a small jug into the drain holes at the bottom and you should see the water come out underneath all you have is just 1 more month. within that, you should purchase a larger tank and complete the nitro cycle, then shift your angels. 1 angel requires min. 30gallons. so, for your 3 angels you have to have a min. 75gallons, or atleast 60-65 gallons and nothing lesser.
it will really make a difference! as the angels become adults, they would more territorial and would defend it with real aggression. esp., when there is a breeding pair, the aggression will be more. so, a larger tank would allow them to co-exist peacefuly, with their own territorries. solved via email! for others reaching this thread, note that any tx you send via a defender relayer has a ttl, which defaults to 8hs. after it expires, defender will automatically invalidate it and replace it with a noop tx with a fast gas price, that will unstuck your tx queue. read more [here](https://docs.openzeppelin.com/defender/relay#valid-until)! v = (4/3)πr³ 

dv/dt = 4πr².dr/dt

so, when the diameter is 20 cm we have:

-4π = 4πr².dr/dt

hence, dr/dt = -1/r²

i.e. dr/dt = -1/10² => -1/100

now, d = 2r

so, d(d)/dt = 2.dr/dt

=> d(d)/dt = -1/50 cm/hour

or, -0.2 mm/hour

:)> (i) here current (i) = 1 a, resistance (r) = 300 ohm, time(t) = 1hwe know thatp = i2r = 12 x 300 = 300 we = p x t = 300 x 1 = 300 wh(ii) here current (i) = 2 a resistance(r) = 100 ohm, time (t) = 1hwe know thatp = i2r = 22 x 100 = 400 we = p x t = 400 x 1 = 400 whhence, in case (ii), the electrical energy consumed per hour is more. depending on the hotel, it can take 1 to 8 business days from the end of your stay for the hold to be released and your funds to become available again. you can sign up for automatic account notifications to find out immediately when your money is released: https://www.greendot.com/greendot/account/alert.