Some integers are marked on a board as shown below. What is the range of these integers?

Hint: From the question it is now known that the range of the given integer set should be found. In general the range of a given set is the difference between the highest and the lowest values of the set. It would always be suggestible to first arrange the given values in an increasing or decreasing order by which the highest and lowest values can be identified with ease.

Complete step-by-step answer:
Now let’s start by counting the number of values given in the set
 There are 8 values that should be arranged in an increasing or decreasing order
Let us arrange them in increasing order
It is clear that we have two negative values which are -17 and -15 out of which -17 is the smallest
So for now our arrangement would be -17, -15
Then comes 0
Which implies that our arrangement now would be -17,-15, 0.
Now 3 would be followed by the rest positive values in an increasing order

Therefore the arrangement of the given values in an increasing order is
-17,-15, 0, 3, 9, 17, 19, 20.
The highest value = 20
The lowest value = -17
\[\begin{align}
  & Range=highest\ value-lowest\ value \\
 & Range=20-\left( -17 \right) \\
 & Range=20+17 \\
 & Range=37 \\
\end{align}\]
Therefore, the range of the given set of values in 37.

Note: If in the given set of values we don’t convert them into an increasing or decreasing order then we might miss some of the values and we wouldn’t get the appropriate highest and lowest values of the set that results in a wrong answer. It would be easy if we identify the negative values first as they would be the lowest values.