Megan and her twin April are seniors in high school. They worked throughout the summer to have enough money to buy cars, and it cost them every cent they had saved! Now they are trying to figure out how much it will cost them to run through the year. “I have no idea how much I will drive this year,” says Megan. “It’s 5 miles to school, I have soccer practice 3 times a week, which is 2 miles from school, and I probably drive 20 miles on the weekend.”“I’m about the same as you. Don’t forget in the summer we will probably each drive about a hundred miles a week.” Estimate how many miles Megan and April will each drive in the next 12 months.

1. Just give one estimate for them both as they drive about the same number of miles.

“Great. So how much do you think gas will cost us this year?” asks Megan. “Talk for yourself. My car runs on electricity! I only need to pay $0.12 per kilowatt hour, and it takes about 1 kilowatt hour to drive 3 miles,” says April.

2. Estimate April’s electricity cost for the upcoming year.

“Well, that’s confusing,” replies Megan. “They say my car gets 25 mpg highway and 17 mpg city. We don’t really live in a city, do we? Gas is currently $2.85 a gallon.”

3. Estimate Megan’s costs for the upcoming year.

Guest Apr 6, 2021

edited by
Guest
Apr 6, 2021

#1**+2 **

1)

Per week, let's say she goes to school 5 times a week, which is reasonable. So she spends 5 miles to school*5 days=25 miles for school. But, she needs to drive back, so 2*25 miles for school=50 miles for school. Also, her soccer practice is 2 miles, so it's 2 miles*3 days=6 miles. So the total per week is 50+6=56. But wait! She drives 20 miles on the weekend. So the total per week is 56+20=76 miles. Let's estimate 52 weeks per year, so there would be 39 weeks of school(school is about 3/4 of the year), so there would be 76*39

$\approx$80*40=3200 miles per year. But wait! She still drives in the summer 100 miles per week for about 13 weeks, so the total is 3200+13*100=$\boxed{4500}$ miles per year.

2)

Because 3 miles is 1 kilowatt hour, we have that April spends $\frac{4500}{3}=1500$ kilowatt hours. Because it is 0.12 dollars per kilowatt hour, we have that the electricity cost is $0.12(1500)=\boxed{180}$ dollars on electricity (feel free to round this yourself)

3)

Assuming that Megan lives on a highway and not city, so she gets 25 miles per gallon. So this means Megan spends $\frac{4500}{25}=180$ gallons of gas. Because she spends 2.85 dollars per gallon, her total cost is $2.85(180)=\boxed{513}$ dollars on gas costs (feel free to round this yourself)

RiemannIntegralzzz Apr 6, 2021

#1**+2 **

Best Answer

1)

Per week, let's say she goes to school 5 times a week, which is reasonable. So she spends 5 miles to school*5 days=25 miles for school. But, she needs to drive back, so 2*25 miles for school=50 miles for school. Also, her soccer practice is 2 miles, so it's 2 miles*3 days=6 miles. So the total per week is 50+6=56. But wait! She drives 20 miles on the weekend. So the total per week is 56+20=76 miles. Let's estimate 52 weeks per year, so there would be 39 weeks of school(school is about 3/4 of the year), so there would be 76*39

$\approx$80*40=3200 miles per year. But wait! She still drives in the summer 100 miles per week for about 13 weeks, so the total is 3200+13*100=$\boxed{4500}$ miles per year.

2)

Because 3 miles is 1 kilowatt hour, we have that April spends $\frac{4500}{3}=1500$ kilowatt hours. Because it is 0.12 dollars per kilowatt hour, we have that the electricity cost is $0.12(1500)=\boxed{180}$ dollars on electricity (feel free to round this yourself)

3)

Assuming that Megan lives on a highway and not city, so she gets 25 miles per gallon. So this means Megan spends $\frac{4500}{25}=180$ gallons of gas. Because she spends 2.85 dollars per gallon, her total cost is $2.85(180)=\boxed{513}$ dollars on gas costs (feel free to round this yourself)

RiemannIntegralzzz Apr 6, 2021