Question 1167383
.
Assume  that when adult with smartphone are randomly selected, 43% use them in meeting or classes. 
If 10 adults smart phone users are randomly selected, find the probability that at least 7 of them 
use their smartphone in meeting or class
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<pre>
This is a Binomial distribution problem.


The number of trials is n=10; the number of successful trials is k >= 7;
the probability of success of every individual trial is p = 0.43.


Use the  complement probability formula   P(k >= 7) = 1 - P(k <= 6).


Use the binomial cumulative probability function binomcdf of calculator TI-84/87

    P(k <= 6) = binomcdf(n,p,k) = binomcdf(10, 0.43, 6) = 0.9194.


Thus the  <U>ANSWER</U>  to the problem's question is

    P(k >= 7) = 1 - 0.9194 = 0.0806.
</pre>

Solved.



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Today, 07/24/2025, I placed this problem to Google AI.


The Google AI produced INCORRECT answer P = 0.0908.


The link to this Google wrong solution is


https://www.google.com/search?q=Assume+that+when+adult+with+smartphone+are+randomly+selected%2C+43%25+use+them+in+meeting+or+classes.+If+10+adults+smart+phone+users+are+randomly+selected%2C+find+the+probability+that+at+least+7+of+them+use+their+smartphone+in+meeting+or+class&rlz=1C1CHBF_enUS1071US1071&oq=Assume++that+when+adult+with+smartphone+are+randomly+selected%2C+43%25+use+them+in+meeting+or+classes.++If+10+adults+smart+phone+users+are+randomly+selected%2C+find+the+probability+that+at+least+7+of+them++use+their+smartphone+in+meeting+or+class&gs_lcrp=EgZjaHJvbWUyBggAEEUYOdIBCTE4NTJqMGoxNagCCLACAfEF1pb2b0cJQX8&sourceid=chrome&ie=UTF-8



- - - - - - - - - - - - - - - - S H A M E L E S S - - - - - - - - - - - - - - - -



Naturally, I posted this my note to them via their feedback system to let them know about their fault.



Looking into MANY problems on binomial distribution, solved by Google AI, 
I regularly see their computational errors - so, my conclusion/impression
is that they permanently use inadequate calculator/solver for such computations,
which DOES NOT provide the necessary precision. They even do not recognize it !



&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Dear developers of the Google AI:


Your illiteracy in performing such calculations is far out of any appropriate scale.



I regularly detected and noticed these computational errors just for several months, 
but I do not see any move/effort from their side to fix this deficiency.