A method currently used by doctors to screen women for possible breast cancer fails to detect cancer in 15% of the women who actually have the disease.

A new method has been developed that researchers hope will be able to detect cancer more accurately.

A random sample of 80 women known to have breast cancer are to be screened using the new method.

At the 0.05 level of significance, the researchers will be able to conclude that the new method is better (i.e. has a lower failure rate) than the one currently in use if the appropriate test statistic has a value:

ANSWERS

Greater than 1.96 in absolute value

Less than -1.96

Greater than 1.645

Less than -1.645

Greater than 1.96