A definite relationship exists among the numbers in each series.

Extend each series below through combinations of addition, subtraction, multiplication and division.

a. 73, 76, 70, 73,__ ,__

b. 400, 200, 600, 300,__ ,__

c. 1, 3, 6, 8, 16,__ ,__

d. 200, 100, 500, 250, 1,250,__ ,__

e. 8, 11, 15, 18, 22,__ ,__

f. 180, 60, 360, 120,__ ,__

g. 100, 400, 200, 800,__ ,__

h. 260, 130, 120, 60,__ ,__