1, 1, 2, 3, 5, 8, 13, 21, 34, . . .
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07 Sep 2022, 01:45
F11=F9+F10 = 34+55 = 89
Thus Quantity B is Greater. Answer: B
The answer is B and it's simple. But I want to give a detailed explanation of this so that other similar problems can be tackled. So here we go.
1st of all this is neither a Geometric nor Arithmetic Sequence so we can't use any of those tricks here. We have to build it using the basic concept of defining Sequences.
If we think of it in an inductive way :
We have to think about it in a bottom-up manner. We have to think about it in terms of the 1st term and start building up to the bottom until we reach F11.
F3=F1+F2
F4=F2+F3
F5=F3+F4
....
F11 = F9+F10
If we think of it in a deductive way:
We have to think in a top-down manner. Breaking the actual problem into previous terms. So we start with F11 right away.
F11 =F9+F10
= {(F7+F8)+(F8+F9)}
= .........until we reach the base case.
In either case, the formula is simple as I have shown.