csat-suneung 2023 Q3

csat-suneung · South-Korea · csat__math 3 marks Geometric Sequences and Series Finite Geometric Sum and Term Relationships
A geometric sequence $\left\{ a _ { n } \right\}$ with positive common ratio satisfies $$a _ { 2 } + a _ { 4 } = 30 , \quad a _ { 4 } + a _ { 6 } = \frac { 15 } { 2 }$$ What is the value of $a _ { 1 }$? [3 points]
(1) 48
(2) 56
(3) 64
(4) 72
(5) 80 
A geometric sequence $\left\{ a _ { n } \right\}$ with positive common ratio satisfies
$$a _ { 2 } + a _ { 4 } = 30 , \quad a _ { 4 } + a _ { 6 } = \frac { 15 } { 2 }$$
What is the value of $a _ { 1 }$? [3 points]\\
(1) 48\\
(2) 56\\
(3) 64\\
(4) 72\\
(5) 80
Paper Questions
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