Math Is Fun Forum

Um, this problem I found in the deductive proofs chapter is I think really hard, not quite sure how and where to start...

Thx...

(APE and CPB are similar triangles)

Can't believe we don't have a good ol' trivia thread,

These ones are really hard (sorry I was bored or something), so don't worry if you don't know them:
1. What is the national flower of scotland?
2. What was the exact month and year of the first moon landing?
3. How many singles titles has Pete Sampras won?
4. What was the nationality of the astronomer Copernicus?
5. In which city is the United Nations situated?
6. Name two of comedian Sasha Baron Cohen's pseudonyms.
7. Is marble a sedimentary, igneous, or metamorphic rock?
8. What character have actors Harrison Ford, Alec Baldwin, and Ben Affleck all played?
9. What was the first name of Argentinian revolutionary Che Guevera?
10. Australia and the USA are the only two major countries which have not signed which agreement placing restrictions on greenhouse emissions?

No cheating!

This is the thread for Christmas Jokes!

Let me start us off with a nice lame one:

"What is the key to a good christmas dinner?"

I know that an exact value uses '=' and an approximation uses '≈', but what is the sign for an inequality approximation. Is it like, </>/≤/≥ but with the '≈' beneath... or...? As an example, how do you write x < √(2) in decimal format to 2 decimal places?

We are given the formula

To find the sum of any number from 1 to n. Then this question pops up that wants us to find the sum of the integers from 51 to 120. Can this formula be manipulated to give a correct solution or is the only way:

?

Just out of curiosity, is this the correct way of applying sigma notation to the problem?

The owner of a 20 room motel must take in $66000 a year to cover costs and earn a reasonable profit.

a) If the average occupancy level is 70% and the same daily rate is charged for all occupied rooms, what should this rate be (to the nearest dollar)?

≈ $13

b) If the owner decides to charge $3 more than the single occupancy rate if two or more people occupy the room, what should the two rates be (given that on average, two or more people are in 75% of the occupied rooms)?

Well, I've just figured out what the two rates would be: The single occupancy rate and the two or more occupancy rate, but the answers couldn't be as simple as $13 and $16...
Are only 75% of the rooms occupied? What about the other 25%? Singularly occupied? Not at all? I give this question a

I'm really bad at these distance speed time questions -.-:

Georgio and Fred ride their bicycles towards each other from points 12 km apart. Georgio rides 2 km/h faster than Fred and they meet in 1 hour. How fast did each ride?