Raffle Ticket Question

Question

If I have 30 raffle tickets to sell and Ticket 1 is $1, Ticket 2 is $2, and so on, is there an equation to figure out the total price for all 30 tickets?

Answer 1

Yew, the sum of an arithmetic series

S_n = (n/2)(2a₁ + (n - 1)d)

n = number of terms

a₁ = the first term

d = the common difference

For this problem

S₅₀ = (50/2)(2(1) + (50 - 1)1)

S₅₀ = 25(2 + 49)

S₅₀ = 25(51)

S₅₀ = 1,275