The number of terms of an Arithmetic Progression is even.
The sum of the terms in the odd places (First term + Third Term + Fifth Term + ...and so on) is 24;
The sum of the terms in the even places (Second Term + Fourth Term + Sixth Term + ... and so on) is 30; and
The last term exceeds the first by 21/2, then:
What is the arithmetic progression?
The number of terms is given to be even. However, that did not
need to be required -- it can be proved form the other
specifications. If the terms are a, a+d, ..., a+2nd then the odd
places sum to (n+1)(a+nd)=24 and the even places sum to n(a+nd)=30 so
that (n+1)/n=24/30 which is impossible.
Posted by Richard
on 2006-03-23 13:25:20