Question

Find the 98th term for the arithmetic sequence 3,4.2,5.4,6.6,7.8,...

Answer 1

a₁ = 3
a₂ = 4.2

d = a₂ - a₁
= 4.2 - 3
= 1.2

a₉₈ = a₁ + d(n-1)
= 3 + 1.2(98-1)
= 3 + 1.2×97
= 3 + 116.4
= 119.4