There is a bag with only red marbles and blue marbles. The probability of randomly choosing a blue marble is
7
8
.
There are 56 marbles in total in the bag and each is equally likely to be chosen.
Work out how many red marbles there must be.

For a science project, a high school research team conducted a survey of local air temperatures. based on the results of the survey, the found that the average temperatures were around 10 degrees higher than expected. this result was wrong. the trouble with the survey was that most of the locations were exposed to direct sunlight and located over asphalt or sand, which resulted in higher temperatures than normal. this is a classic example of an error in which phase of inferential statistics?