Others Maths Puzzle

The arithmetic sequence a, a+d, a+2d, a+3d, . . ., a+(n−1)d has the following properties:
• When the first, third, and fifth, and so on terms are added, up to and including the last term, the sum is 320.
• When the first, fourth, seventh, and so on, terms are added, up to and including the last term, the sum is 224.

What is the sum of the whole sequence?
(A) 656
(B) 640
(C) 608
(D) 704
(E) 672

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Others Other Question
The numbers from 1 to m are written one after another as follows 1234567…….m. The resulting number is divisible by 3 if m is of the form (n is a natural number):
I. 3n
II. 3n – 1
III. 3n – 2 Sum of five consecutive terms of an increasing geometric progression is 211. It is known that all the five terms are positive integers. Find the number of perfect squares among these five terms.

A. 2 B. 3 C. 4 D. 5