Answer:
nth number ; Tn = -18 n + 103
For the 11 th number : T₁₁ = -18 *11 +103 = -95
For the 100 th number : T₁₀₀ = -18 *100 + 103 = -1697
Step-by-step explanation:
The sequence is given as;
85, 67, 49, ......
This is an A.P with a common difference ,d= -18
The formula for nth term can be written as;
Tn=d*n +???
where d= -18, then Tn= -18*n , Tn = -18 n +?
For;
n =1 ----- Tn = -18*1 = -18 ------but T₁ = 85 , so you add 103 to -18 to get 85
n=2-------Tn = -18*2 = -36------but T₂= 67 , so you add 103 to -36 to get 67
Thus,
For the nth number ;
Tn = -18 n + 103
and
For the 11 th number : T₁₁ = -18 *11 +103 = -95
For the 100 th number : T₁₀₀ = -18 *100 + 103 = -1697
