Question

Complete the following series:20.5 , 15 , 19 , 40.5 , _________

Answer 1

Answer:

35,39

Step-by-step explanation:

20.5,15,19,40.5,35,39

Answer 2

140 is Next number in the series  20.5 , 15 , 19 , 40.5 ,

Tₙ₊₁ = (Tₙ - 5.5) x n  where T₁ = 20.5  and n ≥ 1 , n ∈Z

Given:

• Series
• 20.5 , 15 , 19 , 40.5 , _________

To Find:

• Next number in the series

Solution:

Understand the series and find next number

20.5

20.5 x  1  - 5.5 x 1 =  15

15 x  2   -  5.5 x 2 = 19

19 x 3  -    5.5 x 3 =40.5

40.5 x 4 - 5.5 x 4 = 140

or same can be expressed as

20.5

(20.5 - 5.5) x 1 =  15

(15 - 5.5) x 2     = 19

(19 - 5.5) x 3  = 40.5

(40.5 - 5.5) x 4 = 140

Tₙ₊₁ = (Tₙ - 5.5) x n  where T₁ = 20.5  and n ≥ 1 , n ∈Z