The Full Yard

Time for the new puzzler.

Here it is.

A guy buys a house. The house was perfect. Just what he wanted. So he bought it.

But as luck would have it, the entire back yard was just dirt. Which is not great.

He was planning on having a big 4th of July celebration.

So he goes to the local nursery, and he says to the guy, "Look, I've got to buy some grass. Because it's almost June 1, and I've got to have this party on 4th of July weekend. I want a yard full of grass."

They tell him to get sod. That's too expensive. So they talk about grass and different seeds. They talk over various options.

And then finally, the fellow at the nursery says, "Hey, we have this new product. It just came in a few months ago. You may be interested in it. It's a plug of grass that's about the size of your fist."

"What does it do?" the guy asks.

"You plant this in your lawn in a central location, and every day it doubles in size. Let's see how many you would need."

So he asks the owner of the house to draw a little picture of his backyard with the dimensions. And he looks over the diagram and does the math. And then he says, "Okay, you only need one."

The customer says, "Even if I plant this thing like June 1, by June 30, I'll have a lawn?"

The guy says, "According to my calculations, that is correct."

The customer says, "Great, that's what I'll do then."

The guy says, "One more thing. Then what you have to do is, once the lawn is in place, you have to spray it with this arrester spray so it doesn't continue to grow up the side of your house or consume your car in the driveway. You have to stop the growth with this spray."

The customer says, "You sure you did the math correctly?"

The guy says, "Listen, plant one of these and in 30 days, you'll have a full lawn in your backyard."

The customer says, "Okay great. But just to be on the safe side, I want two."

And the puzzler question is this.

If one would give him a lawn in 30 days, when he buys two, what day must he apply the arrester spray to stop it from subsuming his car, his garage and his kids?

Good luck.

Answer the Puzzler »

Remember last week's puzzler?

A Minute's Time

Puzzler time.

Years ago I was at Boston Logan International Airport.

And while I was there, I happened to see in the crowd an old college chum, and I can't remember his name.

As I'm struggling to find his name in my mind, he disappears into the crowd.

I'm thinking I would like to get reacquainted with him. He was a pretty nice guy, this guy.

All I can remember is that he lived in the Midwest someplace.

So I run to one of the monitors hanging from the ceiling, and I see there are like 11 flights going to various destinations in the Midwest. You know, like Worcester, St Louis, Muncie, Indiana, Racine, Wisconsin, etc, etc. And because I can't remember his name, it's hopeless.

So I have to think of another way to find him.

So, in a minute's time, I come up with a plan, and in two minutes I find him.

How did I do it?