Question

Acrylamide, a possible cancer-causing substance, forms in high-carbohydrate foods cooked at high temperatures. Acrylamide levels can vary widely even within the same type of food. An article appearing in a certain journal included the following acrylamide content (in nanograms/gram) for five brands of biscuits.

346

291

334

276

248

(a)

Calculate the mean acrylamide level (in nanograms/gram).

nanograms/gram

For each data value, calculate the deviation from the mean.

Data Value	Deviations from the Mean
346
291
334
276
248

(b)

Verify that, except for the effect of rounding, the sum of the five deviations from the mean is equal to 0 for this data set. (If you rounded the sample mean or the deviations, your sum may not be exactly zero, but it should still be close to zero.)

The sum of the five deviations from the mean, calculated above, is equal to  .

(c)

Use the deviations from part (a) to calculate the variance (in (nanograms/gram)²) and standard deviation (in nanograms/gram) for this data set. (Round the standard deviation to two decimal places.)

variance (nanograms/gram)²standard deviation nanograms/gram

Answer 1