Question 1:   Specify the formula for the arithmetic progression

Question 2:   Find the twenty-first arithmetic term of the following arithmetic series  $\mathrm{1,1.5,2,...}$

Question 3:   Find the common ratio of geometric progression if the first element is  $2$ ,  and the fifth  $1250$ .

Question 4:   Find the sum of the first hundred members of the arithmetic progression if the first element is  $3$  and the difference is  $5$ .

Question 5:   In geometric progression we have:  $b_1=2$ ,  $q=0.5$ .  Calculate the sum of the first 3 members of the progression.

Question 6:   Find the fifth term of geometric progression  $\mathrm{2,4,8,...}$

Question 7:   In arithmetic progression  $a_7=10$ ,  $a_{11}=16$  calculate the progression difference.

Question 8:   In arithmetic progression  $a_{10}+a_{16}=16$ ,  calculate  $a_{13}$ .

Question 9:   In geometric progression  $b_{10}=3$ ,  find  $b_8\times b_{12}$

Question 10:   Calculate the sum of the first twenty natural even numbers.