maths riddles! :D

Riddle 1)

How can you add eight 8's to get the number 1,000? (only use addition)

2) Two Fathers and Two Sons Riddle

Two fathers and two sons sat down to eat eggs for breakfast. They ate exactly three eggs, each person had an egg. The riddle is for you to explain how

3) Three Guys at A Hotel Riddle

Three guys rent a hotel room for the night. When they get to the hotel they pay the $30 fee, then go up to their room. Soon the bellhop brings up their bags and gives the lawyers back $5 because the hotel was having a special discount that weekend. So the three lawyers decide to each keep one of the $5 dollars and to give the bellhop a $2 tip. However, when they sat down to tally up their expenses for the weekend the could not explain the following details:

Each one of them had originally paid $10 (towards the initial $30), then each got back $1 which meant that they each paid $9. Then they gave the bellhop a $2 tip. HOWEVER, 3 • $9 + $2 = $29

The guys couldn't figure out what happened to the other dollar. After all, the three paid out $30 but could only account for $29.

Can you determine what happened?

answers!

1.The key to this math riddle is realizing that the one place must be zero.
888 +88 +8 +8 +8 =1,000

2.one of the 'fathers' is also a grandfather. Therefore the other father is both a son and a father to the grandson. 

In other words, the one father is both a son and a father.


3.There are many ways of explaining/thinking about this truly brain bending riddle! It all boils down to the fact that the lawyers's math is incorrect. They did NOT spend $9 • 3 + $2. 
They spent exactly $27 dollars. $25 for the room and $2 for the tip. Remember they got exactly $3, in total back.

Another way to think about the answer to this riddle is to just pretend that the bellhop refunded $3 to the lawyers (rather than giving them $5 and receiving $2 back). If the lawyers get $3 back and each takes $1. They they spent exactly $27 dollars.

source: http://www.mathwarehouse.com/riddles/math-riddles.php