Hi, could someone tell me if I've done this correctly?
For the progression 1,4,7,10, .... state the
50th term and the sum of the first 50 terms.
I have 50th term as 148
I have sum of first 50 as 1475...
Cheers.
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Hi, could someone tell me if I've done this correctly?
For the progression 1,4,7,10, .... state the
50th term and the sum of the first 50 terms.
I have 50th term as 148
I have sum of first 50 as 1475...
Cheers.
regarding the sum,
I was shown in a previous thread a while ago that
Sn = n(a1 + an) / 2
so I ended up with 25( 1 + a20)
sorry....just realised my mistake, should have been a50 not a20....it works out now,
thank you.