A tank is filled to 25% capacity with oil, which is a mixture of 25%

Question

A tank is filled to 25% capacity with oil, which is a mixture of 25% WTI Crude Oil and 75% Brent Crude Oil. An additional 400 barrels of WTI Crude Oil are added to the tank, filling 2/3 of the remaining empty space. What is the total amount of WTI Crude Oil in the tank?

A. 425 barrels
B. 437.5 barrels
C. 450 barrels
D. 500 barrels
E. 650 barrels

M31-52

ENGRTOMBA2018 · Answer

Let the total volume of the tank be T ( unit^3 )

Oil in the tank =0.25T

WTI in the 0.25T of oil = 0.25T*0.25=T/16

Now the remainder of the tank = 3T/4 (as 0.25T is with mixture of oils while 0.75 or 3/4 of the tank is only with WTI) has 2/3rds with 400 barrels of WTI

Thus, 2/3*0.75T=T/2=400 barrels

Thus, T=800 barrels and WTI = 400+T/16 = 400+800/16 = 400+50=450 barrels., Choice C is the correct answer.

chetan2u · Answer

capacity=x.. 2/3*(3/4)*x=400..x=800..
WTI = 400+ 800/4*4=450
ans C

mejia401 · Answer

So, calculate the total amount of oil in the tank, from the knowledge that 400 barrels were added. 
 \frac{3}{4}*\frac{2}{3}  =  \frac{400}{x}  
 x = 800

Then, calculate the number of WTI before 400 barrels were added, making it  y  to keep my algebra organized.
 1/4 * 1/4 = \frac{y}{800} 
 y = 50

x + y = 400 + 50 = 450 
Answer C.

Alternatively, if the tank is 800 barrels of oil, then 25% of that is 200, and thefore 25% of that is 50. Thus, 400+50 = 450. A,B, and D are out since there is no 5 in the tens digit.

Thanks,

Bunuel · Answer

Official Solution:

A tank is filled to 25% capacity with oil, which is a mixture of 25% WTI Crude Oil and 75% Brent Crude Oil. An additional 400 barrels of WTI Crude Oil are added to the tank, filling 2/3 of the remaining empty space. What is the total amount of WTI Crude Oil in the tank?

A. 425 barrels
B. 437.5 barrels 
C. 450 barrels 
D. 500 barrels 
E. 650 barrels

Initially, the tank was 25% full. Then, 2/3 of the remaining empty space in the tank, which corresponds to 2/3 of the remaining 75%, was filled with 400 barrels of WTI Crude Oil. Since 2/3 of 75% equals 50%, we know that 50% of the tank's capacity is equivalent to 400 barrels, which means the total capacity of the tank is 800 barrels.
 
At the beginning, the tank contained  0.25*0.25*800=50  barrels of WTI Crude Oil. After adding 400 barrels of WTI Crude Oil, the total amount of WTI Crude Oil in the tank increased to  50 + 400 = 450  barrels.

Answer: C

jgcanada · Answer

Find the size of the tank, T: The tank starts at 25% full, or 75% empty. 2/3 of the empty portion is 400 Barrels. (2/3 * 3/4)T = 400 --> T=800

Initial WTI amount: 1/4 of tank was initially full with a mixture of 1/4 WTI. 1/4 full * 1/4 mixture * 800 Barrels = 50 Barrels of WTI

50 Barrels + 400 Barrels that were added, gives us a total of 450 Barrels, Answer is C.

dcummins · Answer

We are asked to determine how much WTI is in the tank.

2/3 of the remaining (3/4 is remaining- see highlighted part of tank) is filled with 400 barrels

2/3*3/4= 1/2 of the remaining tank = 400 barrels

So the tank's capacity is 800 barrels

We know 25% of the tank has oil in it comprised of 25% WTI and 75% Brent.
So 1/4*800
= 200 *1/4 = 50 contained within the 25% component

So 400 WTI (in remaining component of tank) + 50 in 25% component = 450

mm229966 · Answer

V1 = 25%; WTI 25% & Brent 75%;
V2 = 2/3 * remainder => 75%*2/3 = 1/2 of tank is 400 barrels WTI oil; So the whole tank can contain 800 barrels;

V1 = 800*25%= 200 barrels; 200 * 25% = 50 Barrels of WTI;

400+50 = 450

bumpbot · Answer

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A tank is filled to 25% capacity with oil, which is a mixture of 25%

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