After 4,000 gallons of water were added to a large water tank that was

Question

After 4,000 gallons of water were added to a large water tank that was already filled to 3/4 of its capacity, the tank was then at 4/5 of its capacity. How many gallons of water does the tank hold when filled to capacity?

(A) 5,000
(B) 6,200
(C) 20,000
(D) 40,000
(E) 80,000

(A) 5,000
(B) 6,200
(C) 20,000
(D) 40,000
(E) 80,000

Gnpth · Accepted Answer

Initially the tank is 75% full.

and 4000 gallons are added. then the tank becomes 4/5 or 80% full.

so 5% is 4000. Then the 100% will be

=  4000 *100/5= 80,000 .

Answer is E.

Bunuel · Answer

SOLUTION

After 4,000 gallons of water were added to a large water tank that was already filled to 3/4 of its capacity, the tank was then at 4/5 of its capacity. How many gallons of water does the tank hold when filled to capacity?

(A) 5,000
(B) 6,200
(C) 20,000
(D) 40,000
(E) 80,000

(A) 5,000
(B) 6,200
(C) 20,000
(D) 40,000
(E) 80,000

4,000 gallons of water comprise 4/5 - 3/4 = 1/20, which makes the capacity of the tank equal to 4,000*20 = 80,000 gallons.

Answer: E.

Cosmas · Answer

We can set up the following equation for the info in the question:

3/4 of x+4000=4/5 of x; where x is the capacity of the water tank.

x=80,000

Answer E

We can alternatively work this out using proportion: we know that the additional 4000 gallons account for 4/5-3/4=1/20 of the tank. So if 4000 gallons account for 1/20 of the full tank, then 20/20 of the tank is 80,000.

Still Answer E.

sanjoo · Answer

1/20x=4000..x=80000..

sadovskiya · Answer

x=tank capacity

4000/x = (4/5-3/4)/1
4000 = 1/20(x)
x=80000

Please vote for the best solutions by pressing Kudos button;

nutshell · Answer

Let us assume the total capacity of tank to be x.

Since the tank was already filled to 3/4th(or 75%) of its capacity and 4,000 gallons of water were added to bring it to 4/5 th(or 80%) of its capacity, we can make the following inference:
5% of capacity(80%-75%) = 4000;
(5/100) * x = 4,000
x = 80,000;

Ans is (E).

Bunuel · Answer

SOLUTION

After 4,000 gallons of water were added to a large water tank that was already filled to 3/4 of its capacity, the tank was then at 4/5 of its capacity. How many gallons of water does the tank hold when filled to capacity?

(A) 5,000
(B) 6,200
(C) 20,000
(D) 40,000
(E) 80,000

(A) 5,000
(B) 6,200
(C) 20,000
(D) 40,000
(E) 80,000

4,000 gallons of water comprise 4/5 - 3/4 = 1/20, which makes the capacity of the tank equal to 4,000*20 = 80,000 gallons.

Answer: E.

arunspanda · Answer

After 4,000 gallons of water were added to a large water tank that was already filled to 3/4 of its capacity, the tank was then at 4/5 of its capacity. How many gallons of water does the tank hold when filled to capacity?

(A) 5,000
(B) 6,200
(C) 20,000
(D) 40,000
(E) 80,000

(A) 5,000
(B) 6,200
(C) 20,000
(D) 40,000
(E) 80,000

\frac{3}{4}  of Tank = 75% of Tank

\frac{4}{5}  of Tank = 80% of Tank

Given that, difference between 80% and 75% of Tank is 4000 gallons
Or, 5% of Tank = 4000 gallons

Or, Full capacity of Tank  = 20 * 4000 = 80000  gallons of water

Answer:  (E)

PareshGmat · Answer

Let full capacity of tank = x

3/4th of full capacity  = \frac{3x}{4}

Addition of 4000 gallons  = \frac{3x}{4} + 4000

Given that addition of water takes the level to 4/5th

\frac{3x}{4} + 4000 = \frac{4x}{5}

x = 4000 * 20

= 80000

holeintheboat · Answer

Let x be the capacity of tank

(4/5 - 3/4) x = 4000
(0.8-0.75)x = 4000
0.05 x = 4000
x = 4000 * 20 = 80,000

stonecold · Answer

Nice Question
Here making an algebraic equation =>   X +4000 =  X => X=80000
Smash E

rkoshlyak · Answer

3/4*x+4000=4/5*x
Solving for x, and getting x = 80K

Salsanousi · Answer

Let the currently existing water be x
Total capacity be y

\frac{x}{y} = \frac{3}{4}

\frac{x+4000}{y} = \frac{4}{5}

\frac{x}{y} + \frac{4000}{y} = \frac{4}{5}

\frac{3}{4} + \frac{4000}{y} = \frac{4}{5}

\frac{4000}{y} = \frac{1}{20}

y = 80,000

Answer choice E

Sneha2021 · Answer

Tank is filled to 3/4 capacity, so 1/4 is empty. 
After adding 4000, Tank is filled to 4/5 capacity. 
So T/4 > 4000 (Tank is still not filled to full capacity even after adding 4000)
T>16,000
we can reject atleast A, B using this logic

100mitra · Answer

\frac{3}{4}   x  + 4000 =  \frac{4}{5}   x

\frac{4}{5}   x  -  \frac{3}{4}   x  = 4000

\frac{1}{ 20}  *  x  = 4000

x  =  4000 * 20  =  80,000

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