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MathMagic-10-12 Sample Posting
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PRIMO MATHEMATICS
1) Can you find 2 prime numbers whose sum is prime?
2) Can you find 2 prime numbers whose product is prime?
3) What is the smallest positive number divisible by 1, 2, 3, 4,
5, and 6.
4) What is the smallest non-negative number divisible by 1, 2, 3,
4, 5, and 6.
5) What is the smallest number divisible by 1, 2, 3, 4, 5, and 6.
6) The numbers 24, 25, 26, 27, 28 is a string of 5 consecutive
composite numbers. Can you find another string of five consecutive composite numbers less than 100.
7) What is the longest string of consecutive composites less
than 200.
8) Twin primes are 2 primes that differ by 2. List all twin
primes less than 30.
9) A Mersenne prime is any prime number of the form 2^p - 1,
where p is prime. Find 3 mersenne primes. Is 199 a mersenne
prime? Is 63 a mersenne prime?
10)If a prime is mersenne, then it can
perfect number. A perfect number is
of proper divisors is equal to the
is prime then (2^p - 1)(2^(p-1)) is
least 3 perfect numbers and check.
be used to produce a
any whole number whose sum
number itself. If 2^p - 1
a perfect number. Find at
11)Find the sum of the reciprocals of ALL the divisors of each
perfect number in #10. What do you notice?
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MathMagic-10-12 Sample posting
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STATISTICALLY SPEAKING...
1) Find 3 numbers whose mode is 8 and mean is 10. What is the
median of these 3 numbers?
2) Find the mean median and mode
X Value
| 2
3
4
5
----------|-------------------Frequency | 4
2
5
1
3) Find the mean median and mode
X Value
| 2
3
4
5
----------|--------------------Frequency | 40
20 50
10
4) Based on your results, what can you determine regarding the
mean median and mode for the distributions above?
5) If the distribution continues proportionally as above, what is
the frequency distribution for n=180 observations?
6) A probability mass function (PMF) expresses the frequency of each
observation as a probability rather than a frequency.
Write the probability mass function. Assume that only 2, 3,
4, and 5 are possible.
7) Use your PMF in #6 to find each probability:
A) x<4
B) x>4
C) x=4
D) x is even
E) Which is more likely: x is even or x is odd?
F) The odds of an occurrence = probability it occurs divided
by probability it does not occur. Find the odds of "x is 3."
-----------------------------------------------------------------The above are samples, and are intended to be a guide for generating discussions that will lead to solutions.
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