# Car Full of Coins

Here's your nightly math! Just 5 quick minutes of number fun for kids and parents at home. Read a cool fun fact, followed by math riddles at different levels so everyone can jump in. Your kids will love you for it.

# Car Full of Coins

June 9, 2015

When you buy something that costs, say, \$20, it’s easiest to use a \$20 bill, not 20 little \$1 bills – or worse yet, 2,000 pennies. But that’s what a man in China did last month, when he bought a new car using 660,000 coins. He also threw in 20,000 small bills. The pile of money weighed 4 tons, and covered a 13-foot stretch of the showroom floor. All told, the car was worth about \$100,000 in U.S. money, and the coins were each worth about 16 cents. We’re wondering how he brought all those coins to the car shop if he didn’t yet have a car to drive them there…

Wee ones: Which weighs more, this 4-ton pile of money or a 3-ton elephant?

Little kids: The man collected the coins at his gas station. If he collects 5 coins today, 2 tomorrow and 1 the next day, how many coins does he have?  Bonus: If he needs 18 coins in total to buy a tree-shaped air freshener for his car, how many more coins does he need?

Big kids: If you’re buying tires for your car for \$600 and you pay in \$100 bills, how many bills do you need?  Bonus: If the man paid with 660,000 coins and 20,000 bills, how many pieces of money in total did he hand over?

The sky’s the limit: If the car cost \$100,000 in the U.S. and you paid only with dimes (which are worth 1/10 of a dollar), how many dimes would you need?

Wee ones: The pile of money.

Little kids: 8 coins.  Bonus: 10 more coins.

Big kids: 6 bills.  Bonus: 680,000 pieces.

The sky’s the limit: 1 million dimes, or 1,000,000!

### Laura Overdeck

Laura Bilodeau Overdeck is founder and president of Bedtime Math Foundation. Her goal is to make math as playful for kids as it was for her when she was a child. Her mom had Laura baking while still in diapers, and her dad had her using power tools at a very unsafe age, measuring lengths, widths and angles in the process. Armed with this early love of numbers, Laura went on to get a BA in astrophysics from Princeton University, and an MBA from the Wharton School of Business; she continues to star-gaze today. Laura’s other interests include her three lively children, chocolate, extreme vehicles, and Lego Mindstorms.