Geometric sequences
(the database of solved problems)
All the problems and solutions shown below were generated using the Geometric sequences.
| ID |
Problem |
Count |
| 5101 | Find common ratio ( $ r $ ) in geometic progression if $ a_1 = 80 ~~ \text{and} ~~ a_{ 3 } = 120 $. | 2 |
| 5102 | Find $ a_10 $ of a geometric progression if $ a_1 = 9 ~~ \text{and} ~~ r = \dfrac{ 1 }{ 6 } $. | 2 |
| 5103 | Find $ a_6 $ of a geometric progression if $ a_1 = 5000 ~~ \text{and} ~~ r = \dfrac{ 1 }{ 5 } $. | 2 |
| 5104 | Find first element ( $ a_1 $ ) and a common ration ( $ r $ )
of a geometic progression if $ a_{ 2 } = 48 ~~ \text{and} ~~ a_{ 4 } = 75 $. | 2 |
| 5105 | Find $ a_8 $ of a geometric progression if $ a_1 = \dfrac{ 64 }{ 25 } ~~ \text{and} ~~ r = \dfrac{ 5 }{ 2 } $. | 2 |
| 5106 | Find $ a_7 $ of a geometric progression if $ a_1 = 160 ~~ \text{and} ~~ r = \dfrac{ 1 }{ 2 } $. | 2 |
| 5107 | Find $ a_4 $ of a geometric progression if $ a_1 = 96 ~~ \text{and} ~~ r = \dfrac{ 1 }{ 2 } $. | 2 |
| 5108 | Find $ a_6 $ of a geometric progression if $ a_1 = -8 ~~ \text{and} ~~ r = \dfrac{ 3 }{ 2 } $. | 2 |
| 5109 | Find common ratio ( $ r $ ) in geometic progression if $ a_1 = 27 ~~ \text{and} ~~ a_{ 4 } = 8 $. | 2 |
| 5110 | Find the sum of the first $ 1000000 $ terms of a geometric sequence if $ a_1 = 27 ~~ \text{and} ~~ r = 0.6667 $. | 2 |
| 5111 | Find $ a_7 $ of a geometric progression if $ a_1 = 2 ~~ \text{and} ~~ r = \dfrac{ 5 }{ 2 } $. | 2 |
| 5112 | Find the sum of the first $ 10000 $ terms of a geometric sequence if $ a_1 = 27 ~~ \text{and} ~~ r = \frac{ 2 }{ 3 } $. | 2 |
| 5113 | Find $ a_11 $ of a geometric progression if $ a_1 = \dfrac{ 1 }{ 4 } ~~ \text{and} ~~ r = 3 $. | 2 |
| 5114 | Find the sum of the first $ 20 $ terms of a geometric sequence if $ a_1 = 200 ~~ \text{and} ~~ r = 1.1 $. | 2 |
| 5115 | Find $ a_10 $ of a geometric progression if $ a_1 = 2187 ~~ \text{and} ~~ r = \dfrac{ 1 }{ 3 } $. | 2 |
| 5116 | Find the sum of the first $ 12 $ terms of a geometric sequence if $ a_1 = 3 ~~ \text{and} ~~ r = -2 $. | 2 |
| 5117 | Find $ a_4 $ of a geometric progression if $ a_1 = 10 ~~ \text{and} ~~ r = -4 $. | 2 |
| 5118 | Find the sum of the first $ 10 $ terms of a geometric sequence if $ a_1 = 0 ~~ \text{and} ~~ r = 5 $. | 2 |
| 5119 | Find the sum of the first $ 6 $ terms of a geometric sequence if $ a_1 = 27 ~~ \text{and} ~~ r = -\frac{ 1 }{ 3 } $. | 2 |
| 5120 | Find the sum of the first $ 9 $ terms of a geometric sequence if $ a_1 = 21 ~~ \text{and} ~~ r = -5 $. | 2 |
| 5121 | Find $ a_5 $ of a geometric progression if $ a_1 = \dfrac{ 3 }{ 2 } ~~ \text{and} ~~ r = 3 $. | 2 |
| 5122 | Find $ a_12 $ of a geometric progression if $ a_1 = 1 ~~ \text{and} ~~ r = 4 $. | 2 |
| 5123 | Find the sum of the first $ 8 $ terms of a geometric sequence if $ a_1 = 40 ~~ \text{and} ~~ r = \frac{ 4 }{ 9 } $. | 2 |
| 5124 | Find the sum of the first $ 10 $ terms of a geometric sequence if $ a_1 = 103000 ~~ \text{and} ~~ r = 0.99 $. | 2 |
| 5125 | Find $ a_7 $ of a geometric progression if $ a_1 = 120 ~~ \text{and} ~~ r = 1.1 $. | 2 |
| 5126 | $$ a_1 = \frac{ 1 }{ 2 } ~,~ r = \frac{ 1 }{ 2 } ~,~ a_n = \frac{ 1 }{ 512 } ~,~ n = ? $$ | 2 |
| 5127 | Find the sum of the first $ 9 $ terms of a geometric sequence if $ a_1 = \frac{ 1 }{ 2 } ~~ \text{and} ~~ r = \frac{ 1 }{ 2 } $. | 2 |
| 5128 | Find $ a_9 $ of a geometric progression if $ a_1 = \dfrac{ 1 }{ 2 } ~~ \text{and} ~~ r = \dfrac{ 1 }{ 2 } $. | 2 |
| 5129 | $$ a_1 = \frac{ 1 }{ 2 } ~~,~~ r = \frac{ 1 }{ 2 } ~~,~~ a_1 = ? ~~,~~ r = ? $$ | 2 |
| 5130 | Find $ a_14 $ of a geometric progression if $ a_1 = 6 ~~ \text{and} ~~ r = 2 $. | 2 |
| 5131 | Find the sum of the first $ 5 $ terms of a geometric sequence if $ a_1 = \frac{ 1 }{ 100 } ~~ \text{and} ~~ r = \frac{ 1 }{ 10 } $. | 2 |
| 5132 | Find $ a_13 $ of a geometric progression if $ a_1 = 7 ~~ \text{and} ~~ r = 2 $. | 2 |
| 5133 | Find common ratio ( $ r $ ) in geometic progression if $ a_1 = 1 ~~ \text{and} ~~ a_{ 21 } = 10 $. | 2 |
| 5134 | $$ a_1 = 1 ~,~ r = 1.122 ~,~ a_n = 200 ~,~ n = ? $$ | 2 |
| 5135 | $$ a_1 = 1 ~,~ r = 1.122 ~,~ a_n = 100 ~,~ n = ? $$ | 2 |
| 5136 | Find the sum of the first $ 5 $ terms of a geometric sequence if $ a_1 = -\frac{ 3 }{ 2 } ~~ \text{and} ~~ r = 2.5 $. | 2 |
| 5137 | Find the sum of the first $ 5 $ terms of a geometric sequence if $ a_1 = -\frac{ 3 }{ 2 } ~~ \text{and} ~~ r = 0.66 $. | 2 |
| 5138 | Find $ a_3 $ of a geometric progression if $ a_1 = 2 ~~ \text{and} ~~ r = \dfrac{ 1 }{ 4 } $. | 2 |
| 5139 | Find $ a_3 $ of a geometric progression if $ a_1 = 4 ~~ \text{and} ~~ r = 5 $. | 2 |
| 5140 | Find the sum of the first $ 10 $ terms of a geometric sequence if $ a_1 = 40 ~~ \text{and} ~~ r = \frac{ 13 }{ 10 } $. | 2 |
| 5141 | Find $ a_2 $ of a geometric progression if $ a_1 = 5 ~~ \text{and} ~~ r = 6 $. | 2 |
| 5142 | Find the sum of the first $ 20 $ terms of a geometric sequence if $ a_1 = 3 ~~ \text{and} ~~ r = 3 $. | 2 |
| 5143 | Find the sum of the first $ 5 $ terms of a geometric sequence if $ a_1 = 20000 ~~ \text{and} ~~ r = 1.003 $. | 2 |
| 5144 | Find the sum of the first $ 15 $ terms of a geometric sequence if $ a_1 = 5 ~~ \text{and} ~~ r = 3 $. | 2 |
| 5145 | Find the sum of the first $ 164 $ terms of a geometric sequence if $ a_1 = 1778 ~~ \text{and} ~~ r = 1.016 $. | 2 |
| 5146 | Find the sum of the first $ 5 $ terms of a geometric sequence if $ a_1 = -1 ~~ \text{and} ~~ r = -\frac{ 1 }{ 2 } $. | 2 |
| 5147 | Find $ a_15 $ of a geometric progression if $ a_1 = 32 ~~ \text{and} ~~ r = 2 $. | 2 |
| 5148 | Find the sum of the first $ 15 $ terms of a geometric sequence if $ a_1 = 5 ~~ \text{and} ~~ r = -3 $. | 2 |
| 5149 | Find the sum of the first $ 16 $ terms of a geometric sequence if $ a_1 = 5 ~~ \text{and} ~~ r = -3 $. | 2 |
| 5150 | Find $ a_10 $ of a geometric progression if $ a_1 = 7 ~~ \text{and} ~~ r = \dfrac{ 8 }{ 11 } $. | 2 |