money9111 wrote:If the sequence S has 200 terms, what is the 192nd term of S?

1. The first term of S is -40
2. Each term of S after the first term is 3 less than the preceding term.

Data Sufficiency Answers

Did not have a clue how to set this one up.

OA C

for nth term of any AP seq formulae is
Tn=T1+(n-1)d

d is the common diff b/n two succesive terms

s1) n=192,t1=-40 but d=? hence insuff
s2)n=192,d=-3 but t1=???
hence insuff
hence E

Moved to "Data Sufficiency" section!

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thephoenix wrote:

money9111 wrote:If the sequence S has 200 terms, what is the 192nd term of S?

1. The first term of S is -40
2. Each term of S after the first term is 3 less than the preceding term.

Data Sufficiency Answers

Did not have a clue how to set this one up.

OA C

for nth term of any AP seq formulae is
Tn=T1+(n-1)d

d is the common diff b/n two succesive terms

s1) n=192,t1=-40 but d=? hence insuff
s2)n=192,d=-3 but t1=???
hence insuff
hence E

Combine statement 1 and 2(t1 from s1),will get the solution

money9111 wrote:If the sequence S has 200 terms, what is the 192nd term of S?

1. The first term of S is -40
2. Each term of S after the first term is 3 less than the preceding term.

Data Sufficiency Answers

Did not have a clue how to set this one up.

OA C

GMAT has its favorite few types of sequences to test us on, and the arithmetic progression is one like that. It's a sequence in which each term except the first is obtained from the previous by adding a constant value, known as the common difference of the arithmetic progression. If a for its first term and d for the common difference, then any nth term to the AP could be found by using

a + (n - 1) d formula. Hence, what more we need is a and d.

(1) Only a is known as -40. Insufficient

(2) This, by definition, only tells the value of d as -3. Insufficient

Blended! Done!!

C