A politician claims that 20% of the millions of votes cast for his opponent are fraudulent. To test this claim, an investigator collects a random sample of 90 ballots and contacts the voters whose names appear on the ballots to determine if each ballot is in fact fraudulent. Use a normal approximation to find the probability that less than 10 of the selected ballots turn out to be fraudulent, assuming the politician's claim is correct.

"0.0125" is the right solution.

Step-by-step explanation:

The given values are:

Random sample,

n = 90

Claims,

p = 20%

or,

  = 0.20

By using normal approximation, we get

⇒  

On substituting the values, we get

⇒      

⇒      

Now,

The standard deviation will be:

⇒  

On putting the above given values, we get

⇒      

⇒      

⇒      

⇒      

hence,

By using the continuity correction or the z-table, we get

⇒  

⇒  

⇒  

From table,

⇒  

sup

step-by-step explanation:

sine

step-by-step explanation: