CAT level question 10 from QA4CAT
A sequence of numbers is defined as
2 = an – an–1. Sn is sum upto n terms in this sequence and a3 = 5. How many values m, n exist such than Sm – Sn = 65?

(a) 4
(b) 6
(c) 2
(d) More than 6 possibilities

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