A number x, when added 3 times, is 3x.
When 3x is increased by one, it is 3x+1.
We know that (3x+1) is between -8 and 7.
We can write this as:
[tex]\begin{gathered} -8<3x+1<7 \\ -8-1<3x<7-1 \\ -9<3x<6 \\ -\frac{9}{3}Answer: The number is between -3 and 2.