Taking that internship in a remote mountain lab might not have been the best idea. Pulling that lever with the skull symbol just to see what it did probably wasn't so smart either. But now is not the time for regrets because you need to get away from these mutant zombies...fast. Can you use math to get you and your friends over the bridge before the zombies arrive? Alex Gendler shows how.
Think about the concept of "rate" and how it can be used to solve a problem involving time, distance, and speed.
At first it might seem like no matter what you do, you're just a minute or two short of time, but there is a way. The key is to minimize the time wasted by the two slowest people by having them cross together. And because you'll need to make a couple of return trips with the lantern, you'll want to have the fastest people available to do so. So, you and the lab assistant quickly run across with the lantern, though you have to slow down a bit to match her pace. After two minutes, both of you are across, and you, as the quickest, run back with the lantern. Only three minutes have passed. So far, so good. Now comes the hard part. The professor and the janitor take the lantern and cross together. This takes them ten minutes since the janitor has to slow down for the old professor who keeps muttering that he probably shouldn't have given the zombies night vision. By the time they're across, there are only four minutes left, and you're still stuck on the wrong side of the bridge. But remember, the lab assistant has been waiting on the other side, and she's the second fastest of the group. So she grabs the lantern from the professor and runs back across to you. Now with only two minutes left, the two of you make the final crossing. As you step on the far side of the gorge, you cut the ropes and collapse the bridge behind you, just in the nick of time.
How do you make the number 7 even without addition, subtraction, multiplication, or division?
How can you write down eight eights so that they add up to one thousand?
How can you take 2 from 5 and leave 4?
How many sides does a circle have?
How many times can you subtract the number 5 from 25?
When John was six years old he hammered a nail into his favorite tree to mark his height. Ten years later at age sixteen, John returned to see how much higher the nail was. If the tree grew by five centimeters each year, how much higher would the nail be?
I am four times as old as my daughter. In 20 years time I shall be twice as old as her. How old are we now?
What did one math book say to the other math book?
Lily is a lilypad in a small pond. Lilly doubles her size each day, On the 20th day she covers the whole pond. On what day was Lily half the size of the pond?
There is a clothing store in Bartlesville. The owner has devised his own method of pricing items. A vest costs $20, socks cost $25, a tie costs $15 and a blouse costs $30. Using the method, how much would a pair of underwear cost?
What did the triangle say to the circle?
One is to three as three is to five and five is to four and four is the magic number. What is the pattern?
If a boy blows 18 bubbles, Then pops 6 eats 7 and then He pops 5 and blows 1. How many are left?
The ages of a father and son add up to 66. The father's age is the son's age reversed. How old could they be? (3 possible solutions).
What two whole, positive numbers have a one-digit answer when multiplied and a two-digit answer when added?
Pick a number from 1-10, multiply it by 2, add ten, divide it by 2, now subtract the number that you have from the number you picked. What is it?
You want to boil a two-minute egg. If you only have a three-minute timer (hourglass), a four-minute timer, and a five-minute timer, how can you boil the egg for only two minutes?
81 x 9 = 801. What must you do to make the this equation true?
How much will a 38° angle measure when looked at under a microscope that magnifies ten times?
If 1=5, 2=15, 3=215, and 4=3215. What does 5 equal?