Number Line Problem: Find the Value at the Red Point in -5 to 15 Sequence

Let's pay attention to the numbers on the axis from left to right:

$3,7,11,15$

We'll try to find the common denominator.

Note that if we use the operation +4, we'll reach the sequence of numbers:

$3+4=7$

$7+4=11$

$11+4=15$

Therefore, the red point will be the next exercise:

$-5+4=-1$