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vineetbatra
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Hello,
I see a question in the MGMAT book and not completly sure about one part of the solution.
In sequence Cn, we are given that C3 = 12 and C5 = 3. If each term is = the previous term times a constant number, what is the value of C10
using the formula A1*q^(n-1), where A1 is the first number, q is the constant multiplier and n = number in the sequence.
Joining C3 and C5 I get q^2 = 1/4, so Q = +1/2 or -1/2 and A1 = 48. The book says we need not consider -1/2. The answer for C10 is 3/32, but if I consider -1/2 then 48 * (-1/2)^(10-1), I get -3/32.
Can some one explain why can't we use -1/2.
I see a question in the MGMAT book and not completly sure about one part of the solution.
In sequence Cn, we are given that C3 = 12 and C5 = 3. If each term is = the previous term times a constant number, what is the value of C10
using the formula A1*q^(n-1), where A1 is the first number, q is the constant multiplier and n = number in the sequence.
Joining C3 and C5 I get q^2 = 1/4, so Q = +1/2 or -1/2 and A1 = 48. The book says we need not consider -1/2. The answer for C10 is 3/32, but if I consider -1/2 then 48 * (-1/2)^(10-1), I get -3/32.
Can some one explain why can't we use -1/2.
