Middle School Math Quiz
2 posters
Page 1 of 1
Middle School Math Quiz
From a math magazine. Have fun.
1. After a typist had completed ten letters and addressed the ten corresponding envelopes, a careless intern inserted the letters in the envelope at random, one letter per envelope. What is the probability that exactly nine letters were inserted in the proper envelopes?
2. In a certain tournament, a player must be defeated 3 times to be eliminated. If 512 contestants enter the tournament, what is the greatest number of games that could be played?
3. A bicyclist riding against the wind averages 10 mph travelling from A to B, but with the wind averages 15 mph returning from B to A. How many miles per hour is his average speed for the trip?
4. What is the number of real numbers X such that 25x = xsquared + 144?
5. How many integers x in {1,2,3,4,……99,100} satisfy that xsquared + xcubed is the square of an integer?
1. After a typist had completed ten letters and addressed the ten corresponding envelopes, a careless intern inserted the letters in the envelope at random, one letter per envelope. What is the probability that exactly nine letters were inserted in the proper envelopes?
2. In a certain tournament, a player must be defeated 3 times to be eliminated. If 512 contestants enter the tournament, what is the greatest number of games that could be played?
3. A bicyclist riding against the wind averages 10 mph travelling from A to B, but with the wind averages 15 mph returning from B to A. How many miles per hour is his average speed for the trip?
4. What is the number of real numbers X such that 25x = xsquared + 144?
5. How many integers x in {1,2,3,4,……99,100} satisfy that xsquared + xcubed is the square of an integer?
indophile Posts : 4338
Join date : 20110429
Location : Glenn Dale, MD
Re: Middle School Math Quiz
1. 0. There have to be atleast 2 incorrect insertions.
Mosquito Posts : 706
Join date : 20110428
Re: Middle School Math Quiz
5. 3,8,15,24,35,48,63,80,99. For this condition to satisfy, x+1 has to be a perfect square.
Mosquito Posts : 706
Join date : 20110428
Re: Middle School Math Quiz
PseudoIntellectual wrote:
Your answers to 1, 3, 5 are all correct. However, for 5 instead of writing down the actual numbers that satisfy the conditions you should have said 9 (the number of numbers that satify the condition:)
indophile Posts : 4338
Join date : 20110429
Location : Glenn Dale, MD
Re: Middle School Math Quiz
4. 4 . Quadratic equation has 2 real numbers as a soln and since it is absolute, their negative will be a solution too.
Mosquito Posts : 706
Join date : 20110428
Re: Middle School Math Quiz
Yes. 9,16, 9, 16.PseudoIntellectual wrote:4. 4 . Quadratic equation has 2 real numbers as a soln and since it is absolute, their negative will be a solution too.
indophile Posts : 4338
Join date : 20110429
Location : Glenn Dale, MD
Re: Middle School Math Quiz
Answer for # 2lly out of the tournment
There are 512 players. So 511 players must be defeated 3 times each to be totally out of the tournament. The most the ultimate winner can be defeated is 2 times.
So the greatest number of games that can be played = 511x3 + 2 = 1535.
There are 512 players. So 511 players must be defeated 3 times each to be totally out of the tournament. The most the ultimate winner can be defeated is 2 times.
So the greatest number of games that can be played = 511x3 + 2 = 1535.
indophile Posts : 4338
Join date : 20110429
Location : Glenn Dale, MD
Similar topics
» Middle School Math Quiz
» Middle School Math Quiz
» Middle School Math Quiz
» Middle School Math Quiz (no questions on probability)
» Middle School Quiz
» Middle School Math Quiz
» Middle School Math Quiz
» Middle School Math Quiz (no questions on probability)
» Middle School Quiz
Page 1 of 1
Permissions in this forum:
You cannot reply to topics in this forum

