Final answer:
When the two smallest numbers in a simple random sample are replaced by 30, the mean will decrease, the median may or may not change, the mode will not change, and the range, variance, and standard deviation might change depending on the values of the replaced numbers.
Step-by-step explanation:
The given question states that the two smallest numbers in the simple random sample are replaced by 30. To determine which characteristics will change, we need to consider the measures of central tendency (mean, median, mode) and measures of dispersion (range, variance, standard deviation).
If the two smallest numbers are replaced by 30, the mean will decrease because 30 is smaller than the original values. The median may or may not change, depending on the position of the two smallest numbers in the sample. The mode will not change because it represents the most frequently occurring value.
The range, variance, and standard deviation might also change depending on the values of the two replaced numbers. If the replaced numbers were larger than 30, the range, variance, and standard deviation will decrease. If the replaced numbers were smaller than 30, the range, variance, and standard deviation will increase.