You know those white or yellow lines painted on the road? How long do you think each dash is? Take a guess…they’re actually 10 feet long, and 30 feet apart! Because we look ahead at dashes that are farther away, they look shorter. Road lines were invented by accident in 1911, when a leaky milk wagon dribbled a straight white line on the street. Today’s trucks drag a paintbrush. But the driver still has to drive very straight, or we’ll get wiggly lines — and some very bad driving.
Wee ones: Look around the room. What’s the longest straight line you see?
Little kids: If you press the button so the machine paints for 1 second, then leaves a space for 3 seconds, then paints for 1, then skips for 3, how long does that all take? Bonus: If you lay down next to one of these 10-foot road stripes, how much longer than you would it be? Find out your height in feet!
Big kids: If the 2nd dash you paint is all wiggly, then the 5th dash, then the 8th dash, what number dash is the 7th wiggly one? See if you can get it without counting! Bonus: A gallon of paint can make 180 feet of painted line. If you’re painting 10-foot-long dashes, how many dashes can you paint with 1 gallon?
Answers:
Wee ones: Different for everyone…it might be a door frame, a stripe down a curtain, or the edge of the rug.
Little kids: 8 seconds. Bonus: Different for everyone again… subtract your height in feet from 10.
Big kids: The 20th, since each wiggly dash’s position is 1 less than 3 times its “wiggle count” (so the 7th is 1 less than 7 x 3). Bonus: 18 dashes.
