<PRE><B>Question 812730</B>
Sn = n/2( 2a+(n-1)d)

S10 = 10/2(2a+9d)
245=5(a+9d).................(1)

T10= a+9d
substitute in (1)

S10= 5*t10

245/5 = t10

49 =t10...........................(2)

S10-S9=t10

245-s9=45

S9= 200

200= 9/2(2a+8d)
200=9a+36d.......................(3)

solve equation (1) &amp; (3)

245=10a+45d
200=9a+36d

you will get a=4
and d= 41/9

4
8.56
13.11
17.67
22.22
26.78
31.33
35.89
40.44
45

Add them up you get 245


</PRE>