combinatorics
The number of bacteria in a culture is 1000 and this number increases by 250% every two hours. How many bacteria is present after 24 hours?
sequences and series
What does the sum of all the numerals from the numbers from $100$ up to $1000$ equal to?
arithmetic
1 the number of factor 2''s between 1-1000 is more than 5''s.so u must count the number of 5''s that exist between 1-1000.can u continue?
combinatorics
Question Statement An investor has $$20,000$ to be invested amongst $4$ possible investments. Each investment must be a unit of $$1,000$. If all the money needs to be invested then
algebra precalculus
Given that there are $168$ primes below $1000$. Then the sum of all primes below 1000 is (a) $11555$ (b) $76127$ (c) $57298$ (d) $81722$ My attempt to solve it: We know that below
elementary probability
A big part of this problem is that the "1 in 1000" event can happen multiple times within our attempt. Compare this to if you have a special deck of playing cards with 1000 cards in it, exactly
Why is kg/m³ to g/cm³1 to 1000?
I understand that changing the divisor multiplies the result by that, but why doesn''t changing the numerator cancel that out? I found out somewhere else since posting, is there a way to
$1000$ small cubes are assembled into a larger cube. If one layer of
$1000$ is the number of small cubes in the original cube. Each face of the original cube contains $10times10=100$ small cubes, so the effect of removing the small cubes on all six faces,
probability
A hypothetical example: You have a 1/1000 chance of being hit by a bus when crossing the street. However, if you perform the action of crossing the street 1000 times, then your chance of being
Creating arithmetic expression equal to 1000 using exactly eight 8''s
I would like to find all the expressions that can be created using nothing but arithmetic operators, exactly eight $8$''s, and parentheses. Here are the seven solutions I''ve found (on the Internet)...
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