For an Arithmetic Progression (AP), the sum of first four terms and first eight terms is 288. If the sum of first twelve terms is 480, then what is the sum of first 15 terms of this AP?
Sum of first 13 terms of an arithmetic progression is 312. What is the sum of the first 14 terms, if the first term and the common difference are positive integers?
If x, (x^3+1) and x^4 are in arithmetic progression,then what will be possible sum of 3 terms of arithmetic progression? ( given that x is real number )
First and last term of a geometric progression are 3 and 96. If the sum of all these terms is 189, then find the number of terms in this progression.