Please help with Algebra 2 question? Standard normal distribution and z-scores.

According to a national survey, 16% of U.S. adults use the internet to make telephone calls. In a random survey of 100 adults, what is the probability that at most 20 of them use the internet to make telephone calls?

Question

Please help with Algebra 2 question? Standard normal distribution and z-scores.

According to a national survey, 16% of U.S. adults use the internet to make telephone calls. In a random survey of 100 adults, what is the probability that at most 20 of them use the internet to make telephone calls?

amistre64 · Answer

is this an approximation, or something more exact?

what do you have to play with this on?  ti83?

amistre64 · Answer

if we expand (p+q)^(100),  and add up the first 20 terms we have the solution

anonymous · Answer

She gave us the formulas z=x-μ/σ and σ=sqrt np(1-p)

anonymous · Answer

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