The distance between Omaha and Lincoln is 50 miles. Justin drives a car that gets 30 miles per gallon of gas, and Kayla drives a car that gets 20 miles per gallon. How many more gallons of gas does Kayla use on a round trip from Omaha to Lincoln?
A. 1
B. 1 2/3
C. 2 2/3
D. 3
E. 5
The OA is B.
I'm confused with this PS question. Experts, any suggestion? I'm not sure why that is the correct question. Thanks in advance.
The distance between Omaha and Lincoln...
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First, let's find how many gallons of gas each person uses on a round trip.
We know that the distance from Omaha to Lincoln is 50 miles. Since they're doing a round trip, they are going twice that distance - 50 miles from Omaha to Lincoln and then 50 miles from Lincoln back to Omaha. This gives a 100 mile trip in total.
Justin gets 30 miles per gallon of gas - in other words, he uses 1 gallon every 30 miles. So in a 100 mile trip, he uses
$$100\ miles\ \cdot\frac{1\ gallon}{30\ miles}=\frac{10}{3}\ gallons=3\frac{1}{3}\ gallons$$
Kayla gets 20 miles per gallon of gas - in other words, she uses 1 gallon every 20 miles. So in a 100 mile trip, she uses
$$100\ miles\ \cdot\frac{1\ gallon}{20\ miles}=5\ gallons$$
To find how many more gallons Kayla used than Justin, we can subtract the number of gallons Justin used from the number of gallons Kayla used
$$5\ gallons\ -\ 3\frac{1}{3}\ gallons\ =\ 1\frac{2}{3}\ gallons$$
This gives us the correct answer, B.
We know that the distance from Omaha to Lincoln is 50 miles. Since they're doing a round trip, they are going twice that distance - 50 miles from Omaha to Lincoln and then 50 miles from Lincoln back to Omaha. This gives a 100 mile trip in total.
Justin gets 30 miles per gallon of gas - in other words, he uses 1 gallon every 30 miles. So in a 100 mile trip, he uses
$$100\ miles\ \cdot\frac{1\ gallon}{30\ miles}=\frac{10}{3}\ gallons=3\frac{1}{3}\ gallons$$
Kayla gets 20 miles per gallon of gas - in other words, she uses 1 gallon every 20 miles. So in a 100 mile trip, she uses
$$100\ miles\ \cdot\frac{1\ gallon}{20\ miles}=5\ gallons$$
To find how many more gallons Kayla used than Justin, we can subtract the number of gallons Justin used from the number of gallons Kayla used
$$5\ gallons\ -\ 3\frac{1}{3}\ gallons\ =\ 1\frac{2}{3}\ gallons$$
This gives us the correct answer, B.
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Hi LUANDATO,The distance between Omaha and Lincoln is 50 miles. Justin drives a car that gets 30 miles per gallon of gas, and Kayla drives a car that gets 20 miles per gallon. How many more gallons of gas does Kayla use on a round trip from Omaha to Lincoln?
A. 1
B. 1 2/3
C. 2 2/3
D. 3
E. 5
The OA is B.
I'm confused with this PS question. Experts, any suggestion? I'm not sure why that is the correct question. Thanks in advance.
Let's take a look at your question.
The distance between Omaha and Lincoln is 50 miles, therefore, to take a round trip Justin and Kayla have to cover a distance of 100 miles.
Justin drives a car that gets 30 miles per gallon of gas, Let's find the number of gallons it consumes for 100 miles.
For 30 miles Jason's car consumes gas = 1 gallon
For 1 mile Jason's car consumes gas = 1/30 gallon
For 100 miles Jason's car consumes gas = 100 * (1/30) gallons = 100/30 = 10/3 gallons
Similarly, we will find the number of gallons Kayla's car consumes for covering a distance of 100 miles.
For 20 miles Kayla's car consumes gas = 1 gallon
For 1 mile Kayla's car consumes gas = 1/20 gallon
For 100 miles Kayla's car consumes gas = 100 * (1/20) gallons = 100/20 = 5 gallons
We are asked to find how many more gallons of gas does Kayla use on a round trip from Omaha to Lincoln, so we will subtract the consumption of both the cars.
$$=\ 5-\frac{10}{3}$$
$$=\ \frac{15-10}{3}$$ $$=\ \frac{15-10}{3}=\frac{5}{3}=1\ \frac{2}{3}\ gallons$$
Therefore, Option B is correct.
Hope it helps.
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On a round trip from Omaha to Lincoln Justin uses 100/30 = 10/3 = 3 1/3 gallons, and Kayla uses 100/20 = 5 gallons. Thus, Kaylar uses 1 2/3 more gallons of gas.LUANDATO wrote:The distance between Omaha and Lincoln is 50 miles. Justin drives a car that gets 30 miles per gallon of gas, and Kayla drives a car that gets 20 miles per gallon. How many more gallons of gas does Kayla use on a round trip from Omaha to Lincoln?
A. 1
B. 1 2/3
C. 2 2/3
D. 3
E. 5
Answer: B
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