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Sum of Consecutives

What is the sum of the numbers in the following list which are consecutive?

15  5 10 28
24  7 18 26
11 21 17 13
22  9  1 20

The consecutive numbers are: 9, 10, 11; 17, 18; and 20, 21, 22.

The sum of those numbers is 128.

Posted in Brain Teasers

Reverse to Equal Ten

Which two of these rows can be reversed so the total of each row, across and down, equals 10?

A. 5 4 1
B. 6 1 3
C. 3 5 2

Rows B and C, becoming:

A. 5 4 1
B. 3 1 6
C. 2 5 3

Posted in Brain Teasers

A Sign in Japan

This sign was seen in Japan. What does it mean?

A sign seen in Japan

It’s a glass sign containing instructions on a glass door.
It says PULL on one side and PUSH on the opposite side.

Posted in Brain Teasers

Counting Squares

How many squares of any size are in this grid?

4 x 4 grid

30.

There are:

16 1×1 squares
9 2×2 squares
4 3×3 squares
1 4×4 square (the whole shape)

Hence, 16 + 9 + 4 + 1 = 30.

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Four Nines To Make a Hundred

How can you make four 9’s equal 100?

99 9/9 = 100

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Betcha Find a Chocolate

Laura saw that there were three pieces of candy left in a bowl on the kitchen table. She knew they were either chocolates or caramels but didn’t know how many there were of each. What is the probability that there is a piece of chocolate candy in the bowl?

7/8.

The possible combinations are:
1. Chocolate Chocolate Chocolate
2. Caramel Caramel Caramel
3. Chocolate Chocolate Caramel
4. Caramel Caramel Chocolate
5. Chocolate Caramel Caramel
6. Caramel Chocolate Chocolate
7. Chocolate Caramel Chocolate
8. Caramel Chocolate Caramel

Number 2 is the only one that doesn’t have chocolate, thus Laura’s love of chocolate will more than likely be satiated.

Posted in Brain Teasers

The Average of Three

There are three numbers. The first two are 2/3 and 3/4.

What does the third number have to be to make the average of all three be 2?

4 7/12

In order for the average of three numbers to be 2, they must all add up to 6. That gives you this equation:
2/3 + 3/4 + n = 6

Solve for n = 55/12, or 4 7/12.

Posted in Brain Teasers

Two Plus Two Equals Four

Each letter represents a different digit. Any digit can be used, but zero can never start a word. Given W = 2 and R = 6, what do the rest of the letters represent?

  TWO
+ TWO
------
 FOUR

F = 1
O = 8
R = 6
T = 9
U = 5
W = 2

  928
+ 928
-----
 1856
Posted in Brain Teasers

An Urgent Phone Call

A man was working the night shift when he received an urgent phone call, giving him information that caused him to dash home at breakneck speed.

On bursting into his bedroom quite breathless he found his informant was quite correct. His wife was in bed with someone he had never seen before.

However, far from being angry, he greeted them both with a smile and a few hours later brought them both breakfast in bed.

What is the explanation for this odd behavior?

His wife had just given birth.

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Al and Fred’s Car Wash

Al washes a car in 6 minutes. Fred washes the same car in 8 minutes. How long will it take them to wash the car together?

There isn’t enough information, thus there’s no one, right answer. (As frustrating as that may be)

This is from the TV show Boy Meets World, season 1 episode 12.

Posted in Brain Teasers