First you need to determine which type of sequence is this. Because the difference between 2 successive numbers is constant and it is equal to 10 this sequence is geometric one.
d = 10
To calculate what is the value of some member of this sequence you use formula:
An = Ao + (n-1)*d where n represents position of element An, Ao is value of first element in the sequence. Replacing values we get: A110 = -7 + 109*10 A110 = 1083.
