Answer:
36
Step-by-step explanation:
Given that
[tex]R_n = R_{n+1} +3[/tex] is given
First term is 15
This is an arithmetic series with a =15 and d =3
If n is the number of terms, then we have
Sum of n terms = 36 xn = 36n
But as per arithmetic progression rule
[tex]S_n = \frac{n}{2} [2a+(n-1)d]\\= \frac{n}{2} [30+(n-1)3]=36n[/tex]
[tex]72 = 30+3n-3\\n-=15[/tex]
When there are n terms we have middle term is the 8th term
Hence median is 8th term
=[tex]a_8 = 15+7(3) \\=36[/tex]
