A florist sold 11, 25, 16, 30, 19 and $x$ bouquets on six days. The median of the six daily sales was 20. What is $x$?

Explanation

1. 01

   Without x the sorted values are 11, 16, 19, 25, 30.

2. 02

   A median of 20 lies between 19 and 25, so x must sit between them as the 4th value.

3. 03

   $\frac{19 + x}{2} = 20$, so $x = 21$.

4. 04

   Check: if x were below 19 the median would be at most 19; if above 25 it would be 22.