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The Bikes and The Bee

Two bikes are traveling toward each other at a constant speed of 10 mph. When the bike are 20 miles apart, a bee flies from the front wheel of one of the bikes toward the other bike at a constant speed of 25 mph. As soon as it reaches the front wheel of the other bike, it immediately turns around and flies at 25 mph toward the first bike. It continues this pattern until the two bikes smush the bee between the two front tires.

How far did the bee travel?

25 miles.

The easiest way to think about this is to consider the time. The bikes will take 1 hour to touch, given that they start 20 miles apart and are each traveling toward each other at 10 mph.

Therefore the bee is buzzing back and forth at 25 mph for 1 hour.

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Debbie’s Dragster

Debbie starts driving her dragster from rest and constantly accelerates to 60 mph in 10 seconds. How far does she travel in those 10 seconds?

1/12 mile

Ten seconds is 1/6 of a minute and 1 minute is 1/60 of an hour, so 10 seconds is 1/360 of an hour.

If you graph her trip with the speed on the y-axis and the time on the x-axis, you get a triangle with height of 60 mph and width of 1/360 of an hour. To calculate the area of the triangle, you multiply 1/2 × 1/360 × 60 = 1/12.

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A Long Bicycle Ride

Hester goes out for an afternoon bicycle ride. She rides for one hour at five miles an hour, then three hours at four miles an hour and finally two hours at seven miles an hour. How many miles did she ride in total?

31 miles.

1 hour at 5 mph = 5 miles
3 hours at 4 mph = 12 miles
2 hours at 7 mph = 14 miles

5 + 12 + 14 = 31 miles

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The Right Combination of Letters and Values

The letters A through H can be assigned the following values to make all the equations true. Find the right combination of letter values.

Values: 1, 4, 5, 7, 9, 14, 16, 21

C + F = G
A + C = F
B + G = D
B + E = H
D + F = H

A = 1
B = 7
C = 4
D = 16
E = 14
F = 5
G = 9
H = 21

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Finding Rhymes in Categories

Find rhymes for each set of words so the first is a category and the rest are items in the category.

For example, LOYALTY: spring, clean, rinse → ROYALTY: king, queen, prince

1. LOIN: mortar, climb, pickle
2. SQUISH: famine, search, doubt
3. GILDING: radium, Bose, hassle
4. THYME: surgery, girder, scrutiny

1. COIN: quarter, dime, nickel
2. FISH: salmon, perch, trout
3. BUILDING: stadium, mosque, castle
4. CRIME: perjury, murder, mutiny

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A Third As Old

Barry is 67 years old. His daughter is 43. When was she 1/3 as old as him?

31 years ago.

Here’s one way to solve it.

Let x = how many years ago

We get this equation: 67 – x = 3 × (43 – x)

Solving for x gives us 31.

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If This Site Had a Phone Number

If this site had a phone number, I would want it to be 743-3537. Why?

Because the numbers on a phone would spell the word RIDDLES.

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8 = S O A S S

What does this represent?

8 = S O A S S

8 = Sides of a stop sign

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Two Days After

What is two days after the day after the day before yesterday?

Tomorrow.

The day before yesterday is two days ago.

The day after the day before yesterday (2 days ago) is yesterday.

And two days after yesterday is tomorrow.

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The Barber of Seville

The Barber of Seville shaves all men living in Seville.
No man living in Seville is allowed to shave himself.
The Barber of Seville lives in Seville.

Who shaves the Barber of Seville?

Nobody. The Barber of Seville is a woman. Female barbers are rare, but they exist.

And for more fun with barbers, check out the Barber paradox.

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