Question

A company is testing a new device to detect certain substances inside suitcases. Currently, the device is accurate 68% of the time for suitcases that have these substances. In a test where half of the 70 test suitcases carry these substances, about how many times will the test identify a suitcase with the substance as not having it?

Answer 1

Hello.

The answer would be 11.

You will divide 70 and 2 to get the substances.

And for not effecting is 1.00 - 0.68 = 0.32


35 x 0.32=11

Have a nice day