25 were vanilla
500 divided by 100 is 5 meaning that one percent is 5 and 5x5 is 25
There are 23535820 combinations that can be made of 35 calculators taken 8 at a time.
Answer:
... Wall, But Is Sliding Down The Wall So That The Vertical Distance Between The Top Of The Pole And The Floor Is Decreasing At A Rate Of 4 Inches Per Second. How Fast Is The Horizontal Distance Between The Bottom Of The Pole And ... A 176 inch pole is leaning up against a wall, but is sliding down the wall so that the ...
Step-by-step explanation:
The answer choices are sufficiently far apart that you can work this backward. The sum will be ...
236,196*(1 + 1/3 + 1/9 + 1/27 + ...)
so a reasonable estimate can be given by an infinite series with a common ratio of 1/3. That sum is
236,196*(1/(1 - 1/3)) = 236,196*(3/2)
Without doing any detailed calculation, you know the best answer choice is ...
354,292
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There are log(236196/4)/log(3) + 1 = 11 terms* in the series, so the sum will be found to be 4(3^11 -1)/(3-1) = 2*(3^11-1) = 354,292.
Using the above approach (working backward from the last term), the sum will be 236,196*(1-(1/3)^11)/(1-(1/3)) = 236,196*1.49999153246 = 354,292
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* If you just compute log(236196/4)/log(3) = 10 terms, then your sum comes out 118,096--a tempting choice. However, you must realize that the last term is larger than this, so this will not be the sum. (In fact, the sum is this value added to the last term.)
