This Week From Bedtime Math: Fill Me Up
What is Bedtime Math? A message from Laura: Bedtime Math is a pretty simple idea: We all know we should read to our kids at night, but what about math? My husband and I have done fun, mischief-loaded math problems with our kids at night for years, and when at age 2 our third child started hollering for his own math problem, we realized we were onto something: In a world where so many people say, "Ewww, math!" we had created a household culture where kids don't just tolerate math, they actually seek it out. Now, every week, we'll be posting a new problem right here on Scholastic Parents!
Getting gasoline for your car is pretty easy. You drive up to a gas station, stick a hose in the hole in the side of your car, squeeze the handle, and watch the numbers spin to count the gallons. But how does the gas get to that hose in the first place? There must be a lot of it – cars pull up to fill their tanks all day – so where is all that gas hiding? For starters, the gas lives in 2 or 3 giant tanks underground, which hold 8,000 to 10,000 gallons each. Big fuel trucks visit the station and, as shown in the picture, connect hoses from their tanks to the tanks underground…whoosh, they fill the tanks with thousands of gallons at once. In the old days it wasn't so easy: before the very first gas station opened in 1905 in St. Louis, people used to buy gas in small amounts at hardware stores and pharmacies. Now, with over 120,000 gas stations across America, we can all fill up much faster.
Now that we've filled up your tank with these fun facts, see if your kids can come up with the answers to these math challenges:
Wee ones: Which holds more gas: an 8,000-gallon tank or a 10,000 tank?
Little kids: If you're filling your car's 30-gallon tank and you have just 1 more gallon to go, how much have you put in so far? Bonus: If you pull up at 2:39 pm and it takes 4 minutes to fill your tank, at what time do you finish?
Big kids: If a station gets 150 cars in one day and each one needs 20 gallons, will a 1/2-full 8,000-gallon tank have enough gas for them? Bonus: If we have exactly 125,000 stations, how many cars does each station serve if they split up the country's 250,000,000 (250 million) cars equally?
Wee ones: The 10,000-gallon tank.
Little kids: 29 gallons. Bonus: 2:43 pm.
Big kids: Yes, because the cars need 3,000 gallons, and the tank has 4,000. Bonus: 2,000 cars each.