A car gets 30 miles to the gallon. If it is modified to use a solar

Question

A car gets 30 miles to the gallon. If it is modified to use a solar panel, it will use only 75 percent as much fuel as it does now. If the fuel tank holds 15 gallons, how many more miles will the car be able to travel, per full tank of fuel, after it has been modified?

A. 112.5
B. 150
C. 337.5
D. 450
E. 500

Kudos for a correct solution.

A. 112.5
B. 150
C. 337.5
D. 450
E. 500

Kudos for a correct  solution .

balamoon · Answer

Solution -
Mileage before modification = 30 * 15 = 450 miles

After modification, 
1 gallon of fuel gets 30/(.75) = 40 miles per gallon.
Mileage before modification = 40 * 15 = 600 miles

Extra Miles Car will travel after modification = 600 - 450 = 150 miles. ANS B

Beat720 · Answer

Before modified: 
1 gallon ------- 30 miles
15 gallons ----   15*30=450   miles

After modified:
  0.75*1=\frac{{3}}{{4}}   gallon ------- 30 miles
--> 15 gallons ----------------   \frac{{15*30*4}}{3}=600   miles
--> after modified, the car is able to travel  600-450=150  more miles. Answer: B

TimeTraveller · Answer

Original mileage = 30 miles/gallon.

Mileage when a solar panel is used = 30/0.75 = 40 miles/gallon.

Capacity of fuel tank = 15 gallons.

Difference: (40*15) - (30*15) = 150. Ans (B).

KS15 · Answer

1 gallon will give 30 miles
Therefore, 15 gallons will give 450 miles
After modification, 0.75 gallons will give 30 miles
Therefore after modification, 15 gallons will give=(15*30)/0.75=600 miles
Answer=600-450=150 
B

MBAHopeful99 · Answer

Currently, the car gets 450 (30*15) miles per tank.

.75x = 30
x = 40

New tank gets 40*15 = 600

B

ashokk138 · Answer

Total miles to the car with full tank = 30 * 15 = 450 miles
After adding the solar panel, (3/4) * x = 30, => x = 40 miles per gallon.
Total miles after modification => 40 * 15 = 600 miles
The question is the difference => 600 - 450 => 150 miles.

Option B

Bunuel · Answer

800score Official Solution:

After the modification, the vehicle will use less fuel, and will be able to travel 30 miles using just 75% of 1 gallon of fuel, or 0.75 gallons. Therefore, it will travel 30/(0.75), or 40 miles, per gallon of fuel.

Thus, it can travel an additional 10 miles per gallon, and an additional 150 miles per full tank.

The correct answer is choice (B).

ShashankDave · Answer

Normal miles/gallon = 30

when it uses 75% fuel per mile, it will travel
 30 * \frac{100}{75} = 40 miles/gallon

Difference per gallon = 10 miles/gallon

Difference on 15 gallons = 15*10 = 150 miles

(B)

NinetyFour · Answer

My thought process if it helps anyone:

mileage = 30 miles/gallon
gas capacity = 15 gallons
total distance travel-able = 450miles

If a solar panel is installed the car will only use 3/4 the amount of fuel. This means the car will be able to travel the same distance at 15*3/4 gallons of fuel. We can setup the equation as such:

450 = (15*\frac{3}{4}) * x

x = 40 miles/gallon
40 * 15 = 600 miles travel-able with the solar panel

600 - 450 = 150 miles

KanishkM · Answer

Was close on this one

Before modification
1 G will be used for 30 miles 
15 G will be used for 450 miles

After modification 
3/4 G will be now used for 40 miles. 4*30/3
15 G will be used for 600 miles

Difference will be 150 miles

B

GMATGuruNY · Answer

At a rate of 30 miles per gallon, the normal distance for the 15-gallon tank = 15*30 = 450 miles.
Since the modified car requires 3/4 as much fuel, it can travel 4/3 of the normal distance -- and increase of 1/3:
 \frac{1}{3} * 450 = 150  miles

B

ScottTargetTestPrep · Answer

The new rate is:

30/(3/4) = 120/3 = 40 miles per gallon

Thus, the car can now travel 40 x 15 = 600 miles on 15 gallons of fuel. Before the modification, the car could travel 30 x 15 = 450 miles on 15 gallons of fuel. Thus, the difference is 600 - 450 = 150 miles.

Answer: B

Fdambro294 · Answer

Rate-Fuel Efficiency (miles per gallon) * Gallons Consumed = Distance

Rate/Fuel efficiency is Inversely Proportional to Gallons consumed over a constant Distance.

We are told that the car will consume 75% as much Gallons = 3/4 * (Gal Consumed)

Over a Constant Distance, to keep the equation balanced, this will result in: (4/3) * (Fuel Efficiency)

Original Fuel Efficiency = 30 mi / 1 gal

NEW Fuel Efficiency = (4/3) * (30 mi/ 1 gal) = 40 mi / 1 gal

Difference in mileage per FULL TANK of gas is found by converting Fuel Efficiency of (miles / gallon) to the Units of ——- (miles) / (tank)

New (miles / tank) - Old (miles / tank) =

(40 m) / (1 gal) * (15 gal) / (1 tank) - (30 m) / (1 gal) * (15 gal) / (1 tank) =

—-take 15 as Common—-

(15) * (40 - 30) =

150 miles/ per tank MORE

-B-

Posted from my mobile device

ZahidPavel · Answer

.75X = 30 miles
X = 30/.75
So, X = 40, and 15 gallons get (40*15) = 600 miles after modification.
And, Now 30*15 gives 450 miles
More miles: 600 - 450 = 150

Ans: B

TamirKalderon · Answer

30 miles per gallon
15 gallons

current miles the car can travel  30 * 15 =  450 miles.

after solar panel:
30 miles = 0.75 gallon.
so after 30 miles, 3/4 gallons of fuel was used.

to calculate how much miles per 1 gallon:
30 / 0.75 =  40 miles per gallon.

if you're having a hard time deciding whether to divide or multiply:
if you think about it, 30 miles took 3 quarters of a gallon, which means every 10 miles is 1/4 gallon. so the actual Mile per gallon has to be more than 30.

with the new enhancement:
40 miles * 15 gallon fuel tank =  600 miles per 1 fuel tank.

Q: How many  more  miles  will the car be able to travel? 
 A: 600 - 450 =  150  
  Answer is B

you can also skip one stage and multiply 450*4/3 and get to 600 miles per fuel tank

bumpbot · Answer

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A car gets 30 miles to the gallon. If it is modified to use a solar

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