Question 1131491


if an old car with a rate of {{{6}}} break-downs every {{{four}}}{{{ weeks}}} that is {{{6}}} per {{{28}}} days

 so that would be {{{6/7}}} per {{{four}}} days


parameter is {{{6/7}}}, so probability of {{{0}}} is {{{e^(-6/7)=0.4244}}}