Silkworm survival after dose of arsenic
Upper quartile of survival times from 80 silkworm larvae = 292 sec
Normal approximation
Simulation
Click Accumulate and take 100 or more samples.
When the error distribution contains 100 or more crosses, click Show 95% bounds for error. These bounds can be added to the estimate to give a 95% confidence interval.
For example, if 95% of estimation errors in the simulation were within about ±8 sec — the exact value varies with the simulation — then a 95% CI would be
292 - 8 to 292 + 8
i.e. between 284 and 300 seconds
Silkworms must be killed after spinning their cocoons since the silk is damaged when the moths break free. Heat is often used to kill the caterpillars, but researchers performed experiments to investigate the toxic action of arsenic. As part of their research, the survival time of fourth-instar silkworm larvae weighing between 0.41 and 0.45 grams was examined after they were given 0.10 mg of sodium arsenate per gram of body weight.