Of the range, the interquartile range, and the variance, the interquartile range is most influenced by an outlying value in the data set.
is that true or false?

False

Step-by-step explanation:

In fact, interquartile range is least affected by the other two range and variance by outliers.

Range is the difference between least and largest value of data. It  measures the skewness using all data points.

Variance is the square of standard deviation and it is defined as, the sum of square of the distance of observation from the mean.

Interquartile range measures the skewness using 50% of the data. It is the difference of the third quartile and first quartile.

Since, End-points are not included to measure interquartile range. Therefore, it is less affected by outlier.

Further, Variance is most affected then range and interquartile range.