A boat has a ladder that has six rungs. Each rung is one foot apart. The bottom rung is one foot from the water. The tide rises at 12 inches every 15 minutes. High tide peaks in one hour.
When the tide is at its highest, how many rungs are under water?
What is the highest product that can be generated by multiplying two numbers while only using each digit once (1 through 9)?
For example, 12345678 * 9 = 111,111,102
I can kill people, or cause great pain.
You eat me.
I can mean you’re crazy.
I hold things together.
I help climbers stay safe.
I can replace a swear.
And I’m on a violin.
People with nut allergies can die from eating nuts. Being hit in the nuts hurts (I speak from experience. Painful, painful experience). You eat nuts (unless you’re allergic, in which case you should run away). If someone says you’re nuts, it doesn’t mean you’re a peanut or an almond. Nuts and bolts hold things together. A climber’s nut or chock wedges into a rock. Instead of swearing, you can say, “Aww nuts!”. And finally, the nut on a violin is a small piece of hard material that supports the strings.
Jim was canoeing on a lake when a sudden thunderstorm blew in tipped his boat. He swam to a rocky island about a mile from his family’s cottage and found a small, abandoned shack. Inside was an old kerosene lamp and a few matches. All the wood on the island was too damp to burn and the lamp was his only means of signaling for help but it only held an inch of kerosene, not enough to reach its short wick. How did he get the lamp burning to summon help?
Knowing kerosene and water wouldn’t mix and kerosene is less dense than water, he dipped the lamp in the lake and filled it with enough water so the kerosene rose to the top to cover the wick. The lamp was still burning an hour later when a motorboat rescued him.
A variation of this brain teaser includes laser printers (they were invented by Gary Starkweather) and bulletproof vests (invented by Casimir Zeglen using silk, though modern vests use Kevlar, so it’s halfway right).
There are two tricks to this one. The first is 1 × 0. But it’s mostly there as a distraction. Yes, 1 × 0 is 0, but that doesn’t affect anything else in the equation. The second, far trickier element is that the lines ending with 1 don’t have a + sign next to them. That means they should be combined with the following line.