In a survey 10 of the voters support a particular referendum

In a survey, 10% of the voters support a particular referendum. If 10 voters are chosen at random, find the probability that at most 3 voters support the referendum. Write your answer as a proportion and round to 3 decimal places. Someone answered .987 but that doesn\'t appear to be accurate

Solution

let X be the no of votar among 10 supports referendum

then X~Bin(10,0.1)

so

P(X<=3)=0.987

the answer is varified and correct